ANNUAL REPORT2009
CORROSION RESEARCH
Materials Science and Engineering

Publishedby
THE CORROSION RESEARCH GROUPHOKKAIDO UNIVERSITY

No. 38

For additional copies and more information, please write to the group members

Prof. T. Ohtsuka: CORROSION ENGINEERING LABORATORY
Prof. H. Habazaki: INTERFACIAL ELECTROCHEMISTRY LABORATORY
Prof. K. Kurokawa: LABORATORY OF HIGH TEMPERATURE MATERIALS
Prof. S. Ukai: LABORATORY OF ADVANCED HIGH-TEMPERATURE
MATERIALS
Prof. T. Yonezawa: LABORATORY OF INTERFACE OF MATERIALS AND
SURFACE
Prof. T. Narita: ADVANCED COATING LABORATORY
Prof. K. Azumi:
Prof. R. O. Suzuki:
Assoc. Prof. K. Fushimi:
Faculty of Engineering, Hokkaido University
Kita 13, Nishi 8, Kita-ku, Sapporo 060-8628, Japan

Prof. F. Watari: BIOMEDICAL, DENTAL MATERIALS AND ENGINEERINGLABORATORY
Graduate School of Dental Medicine, Hokkaido University
Kita13, Nishi7, Kita-ku, Sapporo 060-8586, Japan

CONTENTS
Page
CURRENT ACTIVITIES and PRESENTATIONSCORROSION ENGINEERING LABORATORYINTERFACIAL ELECTROCHEMISTRY LABORATORYLABORATORY OF HIGH TEMPERATURE MATERIALSBIOMEDICAL, DENTAL MATERIALS AND
ENGINEERING LABORATORYLABORATORY OF ADVANCED HIGH-TEMPERATURE MATERIALSLABORATORY OF INTERFACE OF MATERIALS AND SURFACEADVANCED COATING LABORATORY

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25
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38
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63
78

AFFILIATE MEMBERS
Prof. K. Azumi
Prof. R. O. Suzuki
Assoc. Prof. K. Fushimi

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88
94

ABSTRACTS of PUBLICATIONS
Pasive oxide films and their in-situ detection

101

In-situ raman spectroscopy for passive oxide film on iron in neutral borate
solution102

Self –healing ability of conduction polypyrrole coating with artifical defect103

Ion-exchange treatment of glass surface in NaNO3-TINO3 molten salt

104

Electrodeposition of Bi-Sb-Te alloys by pulse electrolysis in AlCl3-NaCl-KCl molten salt

105Electrorefining reaction of sodium in propylene carbonate containing NaPF6 106
Removing of Mg in Al-Mg alloy by calcined powder from used
dry-cell batteries

107

Photoluminescence from passive oxide films on nickel and chromiumby photo-excitation of UV light

108

Effect of oxide film on oxygen reduction current for the platinum alloy
electrode in PEFC

109

Depth profile analysis of thin passive films on stainless steel by glow
discharge optical emission spectroscopy

110

Formation of porous niobium films by oblique angle deposition:
Influence of substrate morphology

111

Improved electrical properties of silicon-incorporated anodic niobium oxide
112
formed on porous Nb-Si Substrate
Anodic Behavior of nickel in acidic perchlorate solution containing Pb2+

113

Effect of sulfuric acid on pit propagation behaviour of aluminium under
AC etch process

114

Preparation of self-organized porous anodic niobium oxide microcone
and thir surface wettability

115

Spark anodizing behaviour of titanium and its alloys alkaline aluminate
electrolyte

116

The influence of thermal treatment on the electronic properties of a-Nb2O5

117

Characterrization of amorphous anodic Nb2O5 nanofilm for gas sensing

118

High proton conductivity in anodc ZrO2/WO3 nanofilms

119

Importance of water content in formation of porous anodic niobium oxide
films in hot phosphate-glycerol electrolyte

120

Optimized observation of tungsten tracers for investigation of fprmationof porous anodic alumina

121

Growth of porous anodic films on sputtering deposited aluminium
incorporating Al-Hf alloy nanolayers

122

Formation of porous aluminum films with isolated columnar structure using
physical vapor deposition for medium-voltage and high-voltage capacitors

123

Formation of anodic films on sputtering-deposited Al-Hf alloys

124

Enchanced proton conductivity of amorphous silicate nanofilms

125

Size-scaling of proton conductivity in amorphous aluminosilicate acidthin films

126

Oxide scale formed on Al-Mg alloys in H2O-containing Atmosphere127

The Influence of Cr Addition on the High Temperature Corrosion of128
CoNiCrAlY Alloys
Reaction Bhavior of commercial steels in molten lead-free solders

129

Formation of Microstructures of Sb-based alloys at minute stress loading130

Corrosion behavior of Fe-based alloys with additional elements
in molten lead-free solders

131

Effect of composition on microstructure of Sn-Ag solders

132

Biointeractive and bioreactive nature of nanomaterials

133

Analysis of wear debris generated from the metal-on-metal hip joint

134

Capture of bacteria by flexible carbon nanotubes

135

Adhesion of human Osteoblast-like cells(saos-2) to carbon nanotube sheets

136

Modification of the dentin surface by using carbon nanotubes

137

Time-dependence and visualization of TiO2 and Pt particle biodistribution
in mice138

Internal distribution of several inorganic microparticles in mice

139

A DFT and MD study on the interaction of carbon nano-materials
with metal ions140

Controlled calcification using polyanionic macromolecules with an active
reaction center analogue of carbonic anhydrase

141

Observation of biodistribution of indium-tin oxide nanoparticles in mice

142

Biodistribution imaging of magnetic nanoparticles in mice compared with
x-ray scanning analytical microscope and magnetic resonance imaging

143

In vivo internal diffusion of several inorganic microparticles throughan oral administration

144

Synthesis and characterization of a water aoluble multi-walled carbon nanotube
145
and its biodistribution in mice
Development of collagen scaffold coated with multiwalled carbon nanotubes

146

Improvement in cell proliferation on silicone rubber by carbon nanotube
coating

147

Culturing osteoblast-like cells on carbon nanotube-coated dish148

Effect of crosslinking agent in nanohydroxyapatite-collagen composite
on ectopic bone formation with BMP-2 application

149

In situ observation of dynamic of liver cells to caron nanotubes and analysis
of cell functions

150

Physical properties of alminosilicate nanotubes, imogolite, as scaffold
and effect on osteoblastic mineralization

151

Surface modification of carbon nanotubes with calcifying solution forbiomedical applications

152

Preparation and properties of thermoplastic-resin-based nanocomposites
for development of esthetic orthodontic wires

153

Early-stage oxidation behavior of Pt-modified γ’Ni3Al-based alloys withand without Hf addition

154

Compositional factors affecting the establishment and maintenance of
Al2O3 scales on Ni-Al-Pt systems

155

The effect of S and Mn on the high-temperature oxidation andscale spallation behavior of low-carbon steels

156

High-temperature strength characterization of advanced 9Cr-OBS ferritic steels
157
Y2O3 evolution and dispersion refinement in Co-base ODS alloys

158

Formation of ultrafine grains in 9Cr-ODS ferritic steel

159

Dissociation-precipitation behavior of particles in Ni nano-crystals

160

Fuel pin irradiation test at up to 5at% burnup BOR-60 foroxide-dispersion-strengthened ferritic steel cladding161

In-pile creep rupture properties of ODS ferritic steel cladding

162

Effects of aluminum on high-temperature strength of 9Cr-ODS steel

163

Advanced structural materials and cladding

164

Super ODS steels R&D for fuel cladding of next generation nuclear system
1) Introduction and alloy design

165

Super ODS steels R&D for fuel cladding of next generation nuclear systems
2)Effect of minor alloying elements

166

Super ODS steels R&D for fuel cladding of next generation nuclear systems
3) Development of high performance attrition tpe ball mill

167

Super ODS steels R&D for fuel cladding of next generation nuclear systems5) Mechanical properties and microstructure

168

Super ODS steels R&D for fuel cladding of next generation nuclear systems6) Corrosion behavior in SCPW

169

Super ODS steels R&D for fuel cladding of next generation nuclear systems7) Corrosion behavior and mechanism in LBE

170

Super ODS steels R&D for fuel cladding of next generation nuclear systems
9) Damage structure evolution under electron-irradiation

171

Super ODS steels R&D for fuel cladding of next generation nuclear systems10) Cladding tube manufacturing and summary

172

In-situ TEM observations of the crystallization process of solution-prepared
MoS2 amorphous particles

173

Sulfonate group-modified FePtCu nanoparticles as a selective probe
for LDI-MS analysis of oligopeptides from a peptide mixture
and human serum proteins

174

In-situ observation of silver nanoparticle ink at high temperature

175

Detailed investigation on the possibility of nanoparticles of various metalelements for surface-assisted laser desorption/ionization mass spectrometry

176

Plugging a Molecular Wire into Photosystem I: Reconstitution of the
Photoelectric Conversion System on a Gold Electrode177

Gold-Nanoparticle-Supported Silicon Plate with Polymer Micelles
for Surface-Assisted Laser Desorption/Ionization Mass Spectrometryof Peptides

178

Basic and Recent Topics of Metal Nanoparticles

179

Palladium nanoparticle seeded electroless metallization of Al/Al2O3 surfaces

180

Growth of multioxide planar film with the nanoscale inner structure via
anodizing Al/Ta layers on Si

181

Growth of porous type anodic oxide films at micro-areas on aluminum
exposed by laser irradiation

182

Effect of Potential, Temperature, and Fluoride Ions on the Repassivation Kineticsof Titanium in Phosphate Buffered Saline Solution with183
the Photon Rupture Method
Metallization of Oxide / Hydroxide Film of Aluminum: the Palladium
Activation Techniques

184

Formation of Three-dimensinal Micro-actuators with Polypyrrole/Gold
Bi-layer Structure

185

Effect of Aspect Ratio of Artificial Pits Formed on Al by PRM
on Localized Corrosion in Chloride Environments

186

Electrochemical Noise Analysis of 13 mass% Cr Stainless Steel HAZ
by Solution Flow Type Micro-droplet Cell- Effect of solution concentratin-

187

The Effect of Surface Condition and Solution Composition on theRepassivation Behavior of Titanium Studied by PRM in Vitro

188

Galvanic Corrosion Behavior of 3003 Aluminum Alloy in Model Tap Water

189

Effect of PWHT on Electrochemical Behavior of Low C – 13%Cr Welded
Joints with the Use of a Solution Flow Type Micro-Droplet Cell

190

Highly Uniform Aluminum Oxy-hydroxide Nanofiber from Porous
Anodic Alumina

191

Effect of the Electrodeposition Temperature on the Cyclic-Oxidation Resistance192
of Ni Aluminide Containing Zr Formed by Molten-Salt Electrodeposition
Experimental and Simulation Study of Uphill Diffusion of Al in a Pt-Coated
γ-Ni-Al Model Alloy

193

Density functional theory study of zinc clusters

194

DFT calculation of surface diffusion of zinc adatom on zinc crystal surface

195

Development of a ph-sensitive film using a porous anodic oxide film on Al

196

Electroless Ni-P deposition on AZ91 D magnesium alloy prepare
by molybdate chemical conversion

197

Direct Reduction of Liquid V2O5 in Molten CaCl2

198

Calciothermic Reduction of TiCl4 Gas during the Electrolysis of CaCl2 Melt

199

Production Methods of Titanium at Present and in Future

200

Calciothermic Reduction and Simultaneous Electrolysis of CaO
in the Molten CaCl2

201

Influence of Current Density to Direct Reduction of TiO2 in Molten CaCl2

202

Direct Metal Production from Oxides by Using Molten Salt Electrolysis of
CaO in CaCl2

203

Direct Production of Ti-29Nb-13Ta-4.6Zr Biomedical Alloy from Oxide
Mixture in Molten CaCl2

204

Lithium ion insertion/extraction performance of Si/C/O composition foemedfrom polyimides containing silicone

205

Preparation of boron-containing carbons from glucose borate complexes
and their capacitive performance

206

Anodic dissolution of titanium in chloride-containing ethylene glycol solution 207
Capacitance behavior of carbonaceous materials derived from KAPTON
films containing small amounts of metallic compounds

208

Depassivation-repassivation of type-312L stainless steel in NaCl solution
investigates by the micro-indentation

209

Limiting current in a flowing electrolyte-type droplet cell

210

The effect of Metal texture on depassivation-repassivation behavior of ironin borate buffer solution investigated by micro-indention

211

Depasivation ph of austenitic stainless steel in NaCl aqueous solution

212

CURRENT ACTIVITIES and PRESENTATIONSCURRENT ACTIVITIES and PRESENTATIONS

15

CRGHU

CURRENT ACTIVITIES and PRESENTATIONS

16

CRGHU

CURRENT ACTIVITIES and PRESENTATIONSCRGHUCORROSION ENGINEERING LABORATORY
Prof. Dr. Toshiaki Ohtsuka
TEL/FAX: +81-11-706-6351
E-mail: ohtsuka@eng.hokudai.ac.jp
Assoc. Prof. Dr. Mikito Ueda
TEL / FAX: +81-11-706-7813
E mail: mikito@eng.hokudai.ac.jp
Ms. Masako Ogura
TEL/FAX: +81-11-706-6351
E-mail: masako@eng.hokudai.ac.jp

Students
Nan Sheng, Resabal Vannie Joy, S. Kaneko, Y. Tabei, S. Tanaka, K. Nishimoto,Y. Numata, Y. Sugawara, K. Yamanaka, K. Wakai, S. Hariyama, K. Honda,
H. Matsunaga, M. Koya, W. Murakami
Our research activities are concerned with corrosion and corrosion preventionof metals and molten salts electrolysis.
Research programs in progress are as follows:(1) New corrosion resistive films consisting of conductive polymers
A conductive polymer coating was applied to corrosion prevention of carbon
steels. A bilayered polypyrrole (PPy) film doped by molybdo-phosphate (MoP)
ions at the inner layer and by organic ions at the outer layer was electrochemicallyformed on the steel plate in aqueous solution containing pyrrole monomer. The
steel sheet can be passivated by oxidative property of the PPy and MoP ions dopedin PPy layer. The passivation is maintained for more than one month in 3.5 %NaCl aqueous solution. The self-healing property of the coated steel was also
examined. When a small failure is inserted on the PPy coated steel, the potential
initially falls down and, however, it recovered to the passive region in a few hours.
It is observed that the failure site is covered by the molybdate layer which is17

CURRENT ACTIVITIES and PRESENTATIONS

CRGHU

assigned by micro-Raman spectroscopy.
(2) In-situ monitoring of corrosion products on zinc alloy coated steels by Raman
spectroscopy
Transient of corrosion products on zinc and zinc-aluminum alloy layer covering
steel in atmosphere were studied during exposure in humidified atmosphere for 3
days by Raman spectroscopy under the in-situ and ex-situ condition. In thepresence of NaCl precipitate, the initial product of ZnO changes to zinc-hydroxycarbonate and zinc-hydroxy chloride were detected followed by the aqueous ZnCl2
surface layer which is formed by absorption of water from the humidified air andby corrosion of Zn. The ratio of the amount between zinc-hydroxy carbonate andzinc-hydroxy chloride depends on the amount of NaCl precipitate. The addition ofaluminum to the coating requires long time periods before the zinc-hydroxide
compounds appear and much decreases the amount of the corrosion product.
(3) Pt monolayer on Pd for application of PEFC cathodeAs the cathode of PEFC with high performance for the oxygen reduction
reaction (ORR), Pt electrode can be used and for decrease of the amount of Pt,
surface coating of Pt on the less expensive metals has been proposed. Pt monolayer
coating on Pd single crystals was prepared as a model electrode for ORR as thefollowing way. Initially the Pd single crystal is covered byunder-potential-deposition (UPD) of Cu in CuSO4 solution and then the Cu UPD
layer is replaced with Pt in K2PtCl4 solution. The current for ORR measured in
0.05 M H2SO4 is compared between the electrodes of the Pd bulk, Pd-Pt alloy, Pd
single crystal covered by Pt monolayer, and Pt bulk. The small efficiency of Pd
electrode for ORR is much improved by the coating of Pt monolayer.
(4) Electrodeposition of Al-Zn alloys in chloride molten salt
Al-Zn-X(X=Mo, Mn) alloys were electrodeposited in AlCl3-NaCl-KCl molten
salt containing ZnCl2 and MoCl3 or MnCl2 for corrosion protection of steel. The
electrodeposition was performed by constant potential electrolysis or potential
pulse electrolysis. The Zn content in the alloy gradually increases from 2 to 95 at%
at potential from -50 to 100 mV (vs. Al/Al(III)). The Mo content increases from 0
to 3 at% at the same potential region. The surface morphology of the deposit was

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CURRENT ACTIVITIES and PRESENTATIONS

CRGHU

flat and, however, some cracks exist in the deposit surface.
(5) Development of functional glass by ion-exchange reaction in molten salt
Glass plates were immersed in a molten salt of NaNO3-TlNO3 at 673-723 K.
During the immersion, ion-exchange was induced at the surface of the glass. By
the reduction of the glass in hydrogen atmosphere, Tl ion changed to metallic Tl
and then the glass exhibited strong light absorption in visible light from 400 to 700
nm wavelength.
(6) Corrosion product of Mg alloys during exposure in humid air
The corrosion products were assigned by Raman spectroscopy and IR
spectroscopy. For the IR measurement, KBr pellet technique and reflection
absorption technique were used. The standard spectra of various magnesium
compounds were measured for this spectroscopy.
(7) Electrorefining of Na for recycling of used Na-S secondary batteries
The Na-S battery developed since a decade years and now will be widely used
for energy storage. The development of a new electro-refining process of metallic
sodium form the used Na-S batteries may be required. We investigated various
non-aqueous electrolytic melts for the process and found that propylene carbonate
was suitable for the electrolytic melt in the process. In the electrorefining
experiment in propylene carbonate, 99.9% pure metallic sodium was yielded fromsimulated mixture of the used Na-S battery.
(8) Property of Rust Layer on Weathering Steels
Rusts were formed on weathering steel exposed in humidified air with
precipitate of Na2SO4 and NaCl at various amounts. The composition of the rust
was determined by Raman spectroscopy under in-situ and ex-situ condition. Whenthe rust was formed in the Na2SO4 precipitate at large amount on the steel,
α-FeOOH covered the whole surface of the steel, and at small amount, it covered
the surface by patch-like and Fe3O4 and γ-FeOOH covered the other part. Whenthe rust was formed in the NaCl precipitate at large amount, β-FeOOH was found19

CURRENT ACTIVITIES and PRESENTATIONS

CRGHUand at small amount, β-FeOOH, Fe3O4, and γ-FeOOH were formed. When one
pursuits the change of the corrosion product under in-situ condition in the presenceof NaCl precipitate at large amount, initially γ-FeOOH was seen, then β-FeOOH
increased, and after 2-3 days, γ-FeOOH again increased. When β-FeOOH isformed, free Cl- is fixed in β-FeOOH and thus the decrease of Cl- concentration in
the surface aqueous layer formed from the humidified air after the long exposure
may induce the secondary formation of γ-FeOOH. The properties of the rusts
formed by various conditions were also examined by Near IR reflection
spectroscopy and AC impedance spectroscopy as well as the amount of water
absorbed.
(9) Corrosion Behavior of Longline Fishing Hooks Coated by Green Solders Free
from Lead
The present fishing hooks are covered by tin-lead solder for enough protection
against corrosion in marine environment. The use of lead may be inhibited infuture and thus the replacement coating may be required. The corrosion andadhesion of tin-silver alloys were investigated. The tin-silver alloys coating on thesteel hook reveals anti-corrosivity in artificial seawater and in costal environment
comparable to the ordinary tin-lead alloy.
Other Activities
Prof. Ohtsuka attended the Asia Steel 2009 held in Pusan/ Korea on May 24-27,
2009 and presented a paper of “Protective Properties of Rust Layers on
Weathering Steel”. He attended International Conf. on Materials Engineering for
Resources (ICMR) 2009 Akita held in Akita/ Japan on October 21-23, 20 andpresented a paper of “Passive oxide films and their in-situ detection”.
Assoc Prof. Ueda attended the ECS annual meeting, Vienna, Austria, Oct.4-9,
2009, and presented a paper entitled by “Na electrodeposition in propylene
carbonate containing NaPF6”.

Presentations
Photoluminescence from anodic oxide film of SUS304 in acidic or neutral solution,

20

CURRENT ACTIVITIES and PRESENTATIONS

CRGHU

Y. Mito, M. Ueda and T. Ohtsuka, Winter Meeting of Hokkaido Branch of Jpn.
Inst. Metals and ISIJ, Muroran, January 22-23, 2009
Deposition potential of sodium in propylene carbonate containing NaPF6, H.
Hayashi, M. Ueda, T. Ohtsuka, Winter Meeting of Hokkaido Branch of Jpn. Inst.
Metals and ISIJ, Muroran, January 22-23, 2009
Electrodeposition of Al-Mn-Zn alloy in AlCl3-NaCl-KCl molten salt containing
MnCl2,ZnCl2, S. Kaneko, M. Ueda, T. Ohtsuka, The Joint Meeting of The
Hokkaido Sections of ECS Jpn, Surf. Finish. Soc. Jpn. and Jpn. Soc. Corros. Eng.,
Sapporo, February 2-3, 2009
Investigation of thickness of ion-exchange layer and immersion duration of glassin molten salt, Y. Aoyama, M. Ueda, T. Ohtsuka, The Joint Meeting of The
Hokkaido Sections of ECS Jpn, Surf. Finish. Soc. Jpn. and Jpn. Soc. Corros. Eng.,
Sapporo, February 2-3, 2009
Ramman spectroscopy of initial rust in weathering steel, S. Tanaka, M. Ueda, and
T. Ohtsuka, The 3rd. student symposium on Hokkaido branch of Spectroscopic
Society of Japan, Sapporo, March 16, 2009
Continuous measurement of corrosion products on Zn-Al alloy plating layer, A.
Saito, M. Ueda and T. Ohtsuka, The 3rd. student symposium on Hokkaido branchof Spectroscopic Society of Japan, Sapporo, March 16, 2009
Electroplating of Al-Mn-Zn alloy in AlCl3-NaCl-KCl molten salt containing
MnCl2 and ZnCl2, S. Kaneko, M. Ueda and T. Ohtsuka, The 119th Meeting of The
Surface Finishing Society of Japan, University of Yamanashi, Kofu, March 16-18,
2009
Electroplating of Al on Mg alloy in ionic liquid, Y. Tabei, M. Ueda and T.
Ohtsuka, The 119th Meeting of The Surface Finishing Society of Japan, Kofu,
March 16-18, 200921

CURRENT ACTIVITIES and PRESENTATIONSCRGHUTransient change of corrosion products on zinc alloy surface finishing steel in-situ measurement of Raman scattering spectroscopy, T. Ohtsuka, The 157th
Spring meeting of ISIJ, Tokyo, March 28-30, 2009
Na electrodeposition in propylene carbonate containing NaPF6 and morphology ofthe electrodeposit, M. Ueda, H. Hayashi and T. Ohtsuka, The 144th Spring
meeting of the Japan institute of metals, Tokyo, March 28-30, 2009
Electroplating of Al-Mn-Zn alloy in chloride molten salt containing MnCl2 andZnCl2, M. Ueda, S. Kaneko and T. Ohtsuka, The 76th meeting of Electrochemical
Society of Jpn., Kyoto, March 29-31 2009
Corrosion resistance and dissolution of PdCo and PtCo alloys as a PEFC cathode,Y. Tamura, M. Ueda and T.Ohtsuka, Zairyo-to-Kankyo 2009, Tokyo, May 22-24,
2009
Effect of Nickel Addition to Steels on the Rust Formed During 1-3 Years Exposure
to Atmosphere, Vannie Joy T. Resabal and T. Ohtsuka, Zairyo-to-Kankyo 2009,
Tokyo, May 22-24, 2009
Protective Properties of Rust Layers on Weathering Steel, T. Ohtsuka, V. J. T.
Resabal, H. Iwasaki, and S. Tanaka, Asia Steel 2009, No. S9-22, Pusan/ Korea,
24-27 May, 2009
Corrosion protection of steel covered by conductive polypyrrole film containing
molybdo-phosphate ion, K. Nishimoto, M. Ueda and T. Ohtsuka, Annual Meeting2009 of Hokkaido branch of The Chemical Society of Japan, Tomakomai, July 11,
2009
Characterization of the rust layer formed on the nickel containing steels, Vannie. J.
T. Resabal, S. Tanaka and T. Ohtsuka, A meeting 2009 of Hokkaido branch of The
Chemical Society of Japan, Tomakomai, July 11, 200922

CURRENT ACTIVITIES and PRESENTATIONSCRGHURaman spectroscopy of initial rust of weathering steel under the dry and wet
condition, S. Tanaka and T.Ohtsuka, Fall Meeting of ECSJ 2009, Tokyo,
September 10-11, 2009
Development of electrorefining process of Na from used Na-S secondary battery,
M. Ueda, Fall Meeting of ECSJ 2009, September 10-11, 2009
Passivation and corrosion protection of steel plate covered by conductive
polypyrrole bi-layer, K. Nishimoto and T. Ohtsuka, The 145th Fall meeting of theJapan institute of metals, Kyoto, September 15-17, 2009
Corrosion protection of steels by conductive polypyrrole film, T. Ohtsuka, The
158th Fall meeting of ISIJ, Kyoto, September 15-17, 2009
In-situ continuous measurement of corrosion products on galvanized steel, A. Saito
and T. Ohtsuka, The 158th Fall meeting of ISIJ, Kyoto, September 15-17, 2009
Effect of electroplating temperature for Al plating on Mg alloys in EMIC-AlCl3
melt, Y. Tabei, M. Ueda and T. Ohtsuka, The 120th Meeting of The Surface
Finishing Society of Japan, Chiba, September 17-18, 2009
Characteristics of cathodic electrodeposition in AlCl3-NaCl-KCl molten salt
containing MoCl3-ZnCl2, S. Kaneko, M. Ueda and T. Ohtsuka, The 120th Meetingof The Surface Finishing Society of Japan, Chiba, September 17-18, 2009
Na electrodeposition in propylene carbonate containing NaPF6, M. Ueda, ECS
216th meeting of ECS, Vienna Austria, October 4-9, 2009
Techniques for prolonging the life time of metals, T. Ohtsuka, Special public
lectures of Hokkaido University, Sapporo, October 17, 2009
Passive oxide films and their in-situ detection, T. Ohtsuka, International Conf. on
Materials Engineering for Resources (ICMR) 2009 Akita, p. 2009, Akita, October
21-23 200923

CURRENT ACTIVITIES and PRESENTATIONSCRGHUElectroplating of Al-Mn-Zn alloy on mild steel in AlCl3-NaCl-KCl, S. Kaneko, M.
Ueda and T. Ohtsuka, The 41th meeting of Molten Salt Chemistry and Technology,
Kyoto, November 19-20, 2009
Electroplating of Al on Mg-Al alloys in EMIC-AlCl3 ionic liquid, Y. Tabei, M.
Ueda and T. Ohtsuka, The 41th meeting of Molten Salt Chemistry and Technology,
Kyoto, November 19-20, 2009
Corrosion protection of steels covered by conductive polypyrrole bi-layer film, T.
Nishimoto, M. Ueda, T. Ohtsuka, Corrosion Dream 2009, The committee ofcorrosion science in Electrochemical Society Japan, Sapporo, December 4, 2009
Recycle of used sodium-sulfur battery, M. Ueda, Eco Products 2009, Tokyo,
December 10-12, 2009

Facilities and Capabilities
Ellipsometer: Rotating-analyzer type of automated ellipsometer with 632.8 nm
wavelength of light.
Potential Modulation Reflectance: Wavelength region from 350 to 800 nm.
Raman Scattering Spectrometer: JASCO R-800T, triple type of spectrometerequipped with an Argon gas laser of 2W power.
Raman Scattering Spectrometer: Bunko Keiki, single type of spectrometerequipped with 532 nm solid laser, cut-edge filter, and high sensitive CCD.
FT-IR Spectrometer: JASCO FT/IR 4200 equipped with MCT detector, IR-RAS
apparatus, and IR microscopy system.
QCM system for in-situ gravimetry of surface layer on metals.
Electrochemical AC Impedance: NF Circuit Design 5020 FRA and 5095 FRA
equipped with a specially designed potentiostat.
ICP atomic emission spectrometer: Thermo i-CAP 6000.
Electrochemistry apparatuses.
Optical Microscopy
Electrochemical Corrosion Rate Monitor System.
Molten salt ion-exchange apparatus for glass.

24

CURRENT ACTIVITIES and PRESENTATIONSCRGHUINTERFACIAL ELECTROCHEMISTRY LABORATORY
Prof. Dr. Hiroki Habazaki
TEL./FAX: +81-11-706-6575
E-mail: habazaki@eng.hokudai.ac.jp
Assoc. Prof. Dr. Yoshitaka Aoki
TEL./FAX: +81-11-706-6752
E-mail: y-aoki@eng.hokudai.ac.jp

Visiting Professor
Prof. Emeritus Dr. Masahiro Seo
TEL./FAX: +81-11-706-6735
E-mail: masaseo@eng.hokudai.ac.jp
Prof. Dr. Soo-Gil Park
E-mail: sgpark@chungbuk.ac.kr

Students
M. T. Tanvir, S. Koyama, S. Yang, S. Ono, S.P. Sah, T. Fujii
Y. Fukunaga, S. Komiyama, K. Ogawa, M. Teraoka, A. Harada, Y. Fang
Y. Konno, S. Tsunekawa, T. Misawa

In July, Professor Soo-Gil Park, Dean of Research Center of Energy Storage,
Chungbuk National University, Korea joined our group as a visiting professor. Dr
Damian Kowalski left our group and he is now working with Professor Patrik
Schmuki, University of Erlangen and Numberg. Mr. Muhammad Tauseef Tanvir
got a PhD degree in September, and returned to Pakistan.
The research activities of the laboratory are directed to the development ofadvanced oxide films and nanomaterials utilizing anodic oxidation process andspin casting. We are also interested in surface analytical techniques with nanoscale
resolution for a better understanding of the interfacial phenomena of metal andsemiconductor electrodes in relation to electrochemical devices for energy storage,

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CURRENT ACTIVITIES and PRESENTATIONS

CRGHU

corrosion, passivation and surface finishing.
Current topics on research are as follows:(1) Proton-conducting oxide nanofilms
Gas-tight silicate and phosphate nanofilms have been prepared by spin
coating and proton conductivity in the nanofilms have been examined after
depositing gold or platinum button electrode. The nanofilms showed efficient
proton conductivity, and interestingly, the conductivity was enhanced markedly by
reducing the film thickness to less than ~100 nm. Such scaling behavior has been
analyzed in terms of a percolation model. We also found a first example of the
proton-conducting anodic ZrO2-WO3 films.
(2) Tailoring of self-organized porous anodic oxides on various valve metals
Recently, we have found that phosphate-glycerol solution at elevatedtemperature is a new electrolyte to form self-organized porous anodic films onvarious valve metals. We have already successfully developed self-organizedporous anodic films on Ti-Si alloys, niobium and aluminum in the hot
phosphate-glycerol electrolyte. Unique microcone-shaped nanoporous anodic
niobium oxide films are also fabricated by simple anodizing in phosphate-glycerol
electrolyte. Superhydrophobicity has been successfully realized using the anodic
oxide microcones. Crystallization of the anodic oxide during anodizing is a key toform the microcone oxide films.
(3) Formation of barrier-type anodic oxide films on niobium and titanium alloys
for capacitor application
Novel anodic oxide films with excellent dielectric properties have been tailoredon non-equilibrium, single phase niobium and titanium alloys for replacing thecurrently used tantalum solid capacitors. Structural modification of the anodic
films by incorporation of alloying elements is a key issue to improve the dielectric
properties. Advanced process using physical vapor deposition has now been
investigated to develop a porous electrode for electrolytic capacitor application.
Utilization of substrate with cellular structure is effective to tailor alloy

26

CURRENT ACTIVITIES and PRESENTATIONSCRGHUnano-columns with controlled gaps between columns. Our findings revealed highpotential of porous non-equilibrium Nb-Si and Ti-Si alloys prepared by PVD
technique for capacitor application.
(4) Spark anodizing for development of thick oxide films with excellent wear andcorrosion resistance
Spark anodizing of titanium alloys has been performed to form hard andadhesive oxide ceramic coating to improve the wear resistance of various titanium
alloys. Similar coatings with high hardness have been developed on Ti, Ti-6Al-4V
and Ti-15V-3Al-3Cr-3Sn. However, the adhesion of the coating developed on
Ti-15V-3Al-3Cr-3Sn was relatively poor. The poor adhesion was associated withvoid formation in the inner layer close to the alloy/film interface. We foundtwo-step spark anodizing improve markedly the adhesion of the coating without
degradation of high wear resistance.
(5) Surface characterization using glow discharge optical emission spectroscopy
Radio frequency glow discharge optical emission spectroscopy (rf-GDOES)
with excellent depth resolution of sub-nanometer scale has been used to analyze
thin anodic films as well as passive films. The excellent depth resolution even for
non-conducting layers and extremely high sputtering rate allow obtaining depth
profiles precisely and quantitatively. Depth profiles of molybdenum species in thepassive films on molybdenum-containing stainless steels have been analyzed toelucidate the role of molybdenum in enhancing the passivity.
Other Activities
In August, Prof. H. Habazaki visited Harbin Engineering University andpresented an invited paper entitled “Template-assisted synthesis of carbon
nanofibers and their electrochemical properties” at 1st Collaborative andCooperative Symposium between Harbin Engineering University and Hokkaido
University. He also attended 216th ECS Meeting, Vienna, Austria in October, andpresented a paper entitled “Efficient Proton Conduction in Anodic ZrO2-WO3
Films”. He was also invited 12th Joint Symposium between Soul National
University and Hokkaido University held in Soul, Korea and 9th International

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CURRENT ACTIVITIES and PRESENTATIONS

CRGHU

Symposium on Nanotech. Materials for Next Generation Green Energy Systemheld at Chungbuk National University in Korea in November.

Presentation
M. Seo, K. Fushimi, H. Habazaki, T. Nakayama, “Polarization Behavior of Nickel
in Acidic Perchlorate and Acetate Buffer Solutions Containing Small Amount of
Pb2+”, 60th ISE Annual Meeting, 16-21 August, Beijing, China (2009).
S. Koyama, Y. Aoki, H. Habazaki, “Interrelationship between structure andcomposition of anodic oxide films formed on Zr-Si alloys”, 60th ISE Annual
Meeting, 16-21 August, Beijing, China (2009).
S. Yang. Y. Aoki, H. Habazaki, “Formation of porous anodic alumina in hot
phosphate-glycerol electrolyte”, 60th ISE Annual Meeting, 16-21 August, Beijing,
China (2009).
D. Kowalski, Y. Aoki, H. Habazaki, “Proton conductivity in amorphous anodic
oxide films of ZrO2-WO3”, 60th ISE Annual Meeting, 16-21 August, Beijing,
China (2009).
H. Habazaki, Template-assisted synthesis of carbon nanofibers and theirelectrochemical properties, 1st Collaborative and Cooperative Symposium between
Harbin Engineering University and Hokkaido University, 10-11 August, Harbin
Engineering University, Haribin (2009).
M. T. Tanvir, Y. Aoki, H. Habazaki, “Electric properties of anodic oxide films
formed on porous Ti-Si single phase alloy”, The 3rd GCOE Int. Symp. on Catalysis
as the Basis for the Innovation in Materials Science –Beyond the Horizon ofMaterials Chemistry -, 14-15 September, Hokkaido Univ., Sapporo (2009).

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CURRENT ACTIVITIES and PRESENTATIONS

CRGHU

D. Kowalski, Y. Aoki, H. Habazaki, “Proton conduction in anodic zirconia
tungstate nanofilms”, The 3rd GCOE Int. Symp. on Catalysis as the Basis for theInnovation in Materials Science –Beyond the Horizon of Materials Chemistry -,14-15 September, Hokkaido Univ., Sapporo (2009).
T. Fujii, Y. Aoki, H. Habazaki, “Formation of Al-Nb alloy nanocolumns by
oblique angle deposition and their application”, The 3rd GCOE Int. Symp. on
Catalysis as the Basis for the Innovation in Materials Science –Beyond the Horizonof Materials Chemistry -, 14-15 September, Hokkaido Univ., Sapporo (2009).
S. Koyama, Y. Aoki, H. Habazaki, “Nanocrystallization and capacitanceenhancement of anodic ZrO2-SiO2 films”, The 3rd GCOE Int. Symp. on Catalysis
as the Basis for the Innovation in Materials Science –Beyond the Horizon ofMaterials Chemistry -, 14-15 September, Hokkaido Univ., Sapporo (2009).
S. Yang, Y. Aoki, H. Habazaki, “Influence of water content on growth of porous
anodic alumina in hot phosphate-glycerol electrolyte”, The 3rd GCOE Int. Symp.
on Catalysis as the Basis for the Innovation in Materials Science –Beyond the
Horizon of Materials Chemistry -, 14-15 September, Hokkaido Univ., Sapporo(2009).
D. Kowalski, Y. Aoki, H. Habazaki, “Efficient Proton Conduction in Anodic
ZrO2-WO3 Films”, 216th ECS Meeting, 4-9 October, Vienna (2009).
H. Habazaki, “Anodic oxide films on valve metals for electrochemical energy
conversion”, 12th Joint Symp. between Soul National Univ. and Hokkaido Univ.,
19 November, Soul National Univ., Soul (2009).
T. Fujii, Y. Aoki, H. Habazaki, “Surface wettability of Al alloy nanocolumnar
films prepared by oblique angle sputter deposition”, 12th Joint Symp. between Soul
National Univ. and Hokkaido Univ., 19 November, Soul National Univ., Soul(2009).

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CURRENT ACTIVITIES and PRESENTATIONS

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S. Yang, Y. Aoki, H. Habazaki, “Growth behavior of nanoporous anodic alumina
films in hot phosphate-glycerol electrolyte”, 12th Joint Symp. between Soul
National Univ. and Hokkaido Univ., 19 November, Soul National Univ., Soul(2009).

Facilities and Capabilities
DC and RF magnetron sputtering: Shimadzu SP-2C, suitable for preparation ofvarious metallic thin films as well as oxide and nitride films.
FT-IR spectrometer: Jasco FT-IR350, equipped with DR and RAS attachments.
Ultramicrotomy: RMC MT-7, suitable for the preparation of electron transparent
TEM sections.
AFM: SII SPA-400 system operating in contact and tapping modes.
Impedance analyzer: Solartron 1260, measureable in the frequency range of 10µHz to 32 MHz.
Contact angle meters: Kyowa Interface Science, Dropmaster system, to evaluate
superhydrophobicity of solid surface.
Q-mass: Balzers Quadstar421 system for mass analysis of gases with mass numberof less than 200.

30

CURRENT ACTIVITIES and PRESENTATIONSCRGHULABORATORY OF HIGH TEMPERATURE MATERIALS
Prof. Dr. K. Kurokawa
Tel+81-11-706-7572, Fax+811-11-706-7119
E-mail: kurokawa@eng.hokudai.ac.jp
Assi. Prof. Dr. A. Yamauchi
Tel+81-11-706-6818, Fax+811-11-706-7119
E-mail: akira-y@eng.hokudai.ac.jp
Visiting Prof. Dr. S. Taniguchi
Tel+81-11-706-7196, Fax+811-11-706-7119
E-mail : s-tanigu@eng.hokudai.ac.jp

Foreign Researcher
Dr. A. K. Nanda Kumar

Students
T. Ito, T. Kurosaki, T. Shoji, H. Takaki, T. Sudiro, T. Sano, T. Kawamoto,
S. Kirai, H. Nakata, T. Inoue, K. Kimura, Y. Fujimoto, T. Yokata

Technical Staffs
Ms. M. Ogura, Ms. E. Ogawa

Research work at “Laboratory of high temperature materials” directs
toward 1) high-temperature corrosion of Cr-Si-Ni and CoNiCrAlY alloys, 2)
microstructures of oxidation scales formed on NiAl-X alloys, 3) structures of oxide
scales formed on carbon steels, stainless steels and aluminum alloys in
H2O-containing atmospheres, 4) scale failure characteristics using acoustic
emission (AE), 5) Sintering and oxidation behavior of nano WC, and 6) corrosion
behavior of iron-based alloys in molten lead-free solders.
Current topics on research are in the following:

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CURRENT ACTIVITIES and PRESENTATIONS

CRGHU(1) High-temperature corrosion behavior of Cr-Si-Ni and CoNiCrAlY alloys
High-temperature corrosion tests of Cr-Si-Ni and CoNiCrAlY alloys
have been examined. Cr added CoNiCrAlY alloys have poor corrosion resistanceto molten Na2SO4 and NaCl salts, compared with CoNiCrAlY alloys. On the other
hand, 30mass%Si added CoNiCrAlY alloy has an excellent corrosion resistance tomolten Na2SO4 and NaCl salts. These results suggest that addition of 30mass% Si
has a good effect on the corrosion resistance of CoNiCrAlY alloy, but the additionof Cr adversely leads to lowering the corrosion resistance of CoNiCrAlY alloys.
(2) Microstructures of oxide scales formed on NiAl-X alloys
In order to clarify the microstructures of oxide scales formed on NiAl-X(X=Mo, Nb) alloys, the oxidation tests in air have been done. Microstructures ofoxide scales formed on NiAl-X alloys are observed by FE-SEM and TEM. The
addition of Mo to the β-NiAl suppresses the scale growth and formation ofinterfacial voids, and improves the adhesion of scale compared with NiAl without
additional elements. It is supposed that the addition of Mo improves the scaleadhesion due to the promotion of transformation of Al2O3 from θ or γ to α. On theother hand, the addition of Nb to the β-NiAl promotes the scale growth and scale
failure. It is suggested that the addition of Nb promotes the growth of the oxide
scale due to the enhancement of outward Al ion diffusion.
(3) High-temperature oxidation of carbon steels, stainless steels and aluminumalloys in H2O-containing atmospheres
In order to clarify the microstructures of oxide scales formed on Mo
added ferritic stainless steels, oxidation tests are being done in H2O-containing
atmospheres. In the ferritic stainless steel without Mo, it is observed that the Cr2O3
scale has large cracks. On the other hand, in the Mo added ferritic stainless steel,
we found a decrease in the number and length of cracks in the Cr2O3 scale. From
the result of TEM-EDS analysis, it is confirmed that the Cr2O3 scale contains alittle bit of Mo. These results suggest that Mo improves the property of Cr2O3 scaleand suppresses the deterioration of scale failure. Similarly, oxidation behavior andscale structures of carbon steels and Al-Mg alloys in H2O-containing atmospheres
are also being investigated.

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CURRENT ACTIVITIES and PRESENTATIONS

CRGHU(4) Scale failure characteristics using acoustic emission (AE)In order to clarify the scale failure characteristics, we have done
acoustic emission (AE) measurements during isothermal oxidation tests andcooling. The results showed that the presence of water vapor and the increase in Si
content in the carbon steel tend to promote the scale failure. Moreover, weinvestigated the influence of cooling rates on the scale failure. Failure
characteristics of scales are attributable to the cooling rate, scale structure, andeutectoid reaction. In general, higher cooling rate leads to higher strain rate andthere may be a temperature gradient across the scale thickness, which would
additionally enhance the scale failure.
(5) Sintering and oxidation behavior of nano WC
To clarify the mechanisms behind the microstructural evolution during
sintering of ultra fine WC and WC-SiC, sintering was interrupted at various
temperatures and the kinetics of grain growth was analyzed. The observations
suggest that there is a preferential wetting of the WC grains by the liquid phase(Si) responsible for the coarsening process. The observed relation between thegrain size and stroke change rate is explained on the basis of the rate equations fordensification and coarsening.
(6) Corrosion behavior of iron-based alloys in molten lead-free solders
The corrosion behavior of low carbon steel-X (X=Cr, Ti and Mo) alloys
in molten Sn-3.0mass%Ag -0.5mass%Cu solders have been investigated. A FeSn2
layer is formed in all the specimens in the interfacial reaction at 623 to 723 K. The
addition of Cr or Ti to the low carbon steel improves the thickness of consumed
substrate due to suppression of interfacial reaction than those without Cr and Ti.
On the other hand, the addition of Mo to carbon steel does not improve theresistance against interfacial reaction because of the formation of Mo rich ferrite
phase which is corroded easily. These results indicate that the microstructure ofmetal substrate has influence on the interfacial reaction. The thickness loss ofcarbon steel with Cr follows a parabolic law.
Other Activities
In August, Prof. Kurokawa attended the International Symposium on
Applied Plasma Science 2009 held in Hamburg, Germany, and presented papers

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CURRENT ACTIVITIES and PRESENTATIONS

CRGHU

entitled “The Influence of Cr Addition on the High Temperature Corrosion of
CoNiCrAlY Alloys”.

Presentations
Influence of oxidation temperature on morphology of oxide scale formed on
Al-Mg alloys; A. Yamauchi, T. Kurosaki, R. Tu, T. Goto and K. Kurokawa: The
Winter Joint Meeting of The Hokkaido Secs. of Jpn. Inst Metals and Iron and SteelInst. Jpn., Muroran, Jan., 2009.
Reaction behavior of commercial steels in molten lead-free solders; A. Yamauchi,
A. Irisawa, S. Kawakubo, K. Kurokawa and J. Tanaka: Mate2009, Yokohama, Jan.,2009.
Formation of microstructures of Sn-based alloys at minute stress loading; H.
Takagi, A. Yamauchi, A. Irisawa, S. Kawakubo, K. Kurokawa and J. Tanaka: ibid.
Variation of cooling rate on cast structure of multi Sn-Ag alloy systems; S. Kirai,
A. Yamauchi, K. Kurokawa and J. Tanaka: 2009 Winter Joint Meeting Hokkaido
Secs. of Chem. Soc. Jpn. And Jpn. Soc. Anal. Chem., Sapporo, Feb., 2009.
Effect of additional element on interfacial growth between Fe-based alloys andmolten lead-free solder; T. Kawamoto, A. Yamauchi, K. Kurokawa and J. Tanaka:ibid.
Formation mechanism of sub-grain structures of lead-free solders; H. Takagi, A.
Yamauchi, K. Kurokawa and J. Tanaka: ibid.
Influence of oxidation temperature on oxide scale formed on Al-Mg alloys; A.
Yamauchi, T. Kurosaki, R. Tu, T. Goto S. Taniguchi and K. Kurokawa: The 143rd
Annual Meeting of Jpn. Inst. Metals, Tokyo, Mar., 2009.
Effect of additional elements on microstructure of oxide scale formed on β-NiAl;
K. Kurokawa, T. Ito, H. Tomoto and A. Yamauchi: ibid.

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CURRENT ACTIVITIES and PRESENTATIONS

CRGHU

Optimum Al content of Al reservoir layer in Ni super alloy/ Re-Cr-Ni(-W) σphase/Al reservoir system; S. Saito, K. Kurokawa, T. Takashima, S. Hayashi and T.
Narita: ibid.
Damage behavior of oxide scale formed on Si containing steel -Effect of Si content
and water vapor-; H. Nakata, A. Yamauchi, S. Taniguchi and K. Kurokawa: The
Summer Join t Meeting of The Hokkaido Secs. of Jpn. Inst Metals and Iron andSteel Inst. Jpn., Muroran, July, 2009.
Influence of molten Na2SO4+ NaCl salts on high temperature corrosion behavior of
STBA21 and Cr-Si-Ni compacts; T. Sano, T. Sudiro, A. Yamauchi, S. Taniguchi
and K. Kurokawa: ibid.
Corrosion behavior of Fe-based alloys in molten lead-free solder; T. Kawamoto, A.
Yamauchi, K. Kurokawa and J. Tanaka: ibid.
Effect of composition on microstructure of Sn-Ag solders; S. Kirai, A. Yamauchi,
A. Irisawa, S. Kawakubo, K. Kurokawa and J. Tanaka: The 19th Symposium of
Micro Electronics, Fukuoka, Sep., 2009.
Corrosion behavior of Fe-based alloys with additional elements in molten lead-freesolders; T. Kawamoto, A. Yamauchi, A. Irisawa, S. Kawakubo, K. Kurokawa and
J. Tanaka: ibid.
The Influence of Cr Addition on the High Temperature Corrosion of CoNiCrAlY
Alloys; T. Sudiro, T. Sano, A. Yamauchi, S. Taniguchi, A. Kobayashi and K.
Kurokawa: 7th International Symposium on Applied Science, Hamburg, Germany,
August, 2009.
Microstructure of oxide scale formed on Al-Mg alloys in H2O-containing
atmospheres; T. Kurosaki, A. Yamauchi and K. Kurokawa: The 144th Annual
Meeting of Jpn. Inst. Metals, Kyoto, Sep., 2009.

35

CURRENT ACTIVITIES and PRESENTATIONS

CRGHUEffect of Mo addition on morphology of Cr2O3 scale formed on ferritic stainlesssteels; T. Shoji, A. Yamauchi, S. Taniguchi, K. Kurokawa, K. Fukuda, S. Ishikawa
and T. Ujiro: ibid.
Effect of various additional elements on morphology of oxide scale formed on
β-NiAl; T. Ito, A. Yamauchi, S. Taniguchi and K. Kurokawa: ibid.
Effect of Si content on damage behavior of oxide scale formed on low carbon
steel; H. Nakata, A. Yamauchi, S. Taniguchi, K. Kurokawa, I. Sohn and J. Choi:
ibid.
Effect of additional elements on Solid solution behavior of γ’ phase in Ni-Al and
Ni-Al-Cr system; S. Saito, K. Kurokawa, T. Takashima, S. Hayashi and T. Narita:
ibid.
Oxidation Behavior of Combustion Synthesized β-SiAlON in Air; X Yi, A.
Yamauchi, K. Kurokawa and T. Akiyama: ibid.
The influence of Cr addition on the high temperature corrosion of CoNiCrAlY
alloys; T. Sudiro, T. Sano, A. Yamauchi, S. Taniguchi and K. Kurokawa: The 56th
Jpn. Conf. on Materials and Environments, Osaka, Sep., 2009.
High temperature corrosion behavior of Cr-Si-Ni compacts in molten Na2SO4+
NaCl salts; T. Sano, A. Yamauchi, S. Taniguchi and K. Kurokawa: ibid.
Corrosion behavior of steel in molten lead-free solder; A. Yamauchi, J. Tanaka andK. Kurokawa: ibid.
Effect of carbide additions on the grain size and mechanical properties of sinteredn-WC; A. K. Nanda Kumar, A. Yamauchi, M. Watabe and K. Kurokawa: The 14th
Meeting on Spark Plasma Sintering, Sendai, Nov., 2009.

36

CURRENT ACTIVITIES and PRESENTATIONSCRGHUFacilities and Capabilities
Spark Plasma Sintering Equipment
Ultra-High Vacuum Furnace with Mass Spectrometer
Oxidation Test Equipment with Thermobalance and Ultra-High Temperature
Furnace
Optical Microscope with High-Temperature Furnace
Micro-Thermobalance
SEM (Carry Scope)
Micro Vickers Hardness Tester
Acoustic Emission System

37

CURRENT ACTIVITIES and PRESENTATIONSCRGHUBIOMEDICAL, DENTAL MATERIALS AND ENGINEERINGLABORATORY
Prof. Dr. F.Watari
Tel&Fax:+81-11-706-4251 E-mail:watari@den.hokudai.ac.jp
Assoc. Prof. Dr. M.Uo
Tel&Fax:+81-11-706-4251 E-mail:uo@den.hokudai.ac.jp
Res. Assoc. Dr. T.Akasaka
Tel&Fax:+81-11-706-4251 E-mail:akasaka@den.hokudai.ac.jp
Res. Assoc. Dr. S.Abe
Tel&Fax:+81-11-706-4251 E-mail:sabe@den.hokudai.ac.jp

Foreign Researchers
Dr. Lu Xiong

Students
M.Matsuoka, E.Hirata, K.Ishikawa, S.Ito, T.Koshikawa, Y.Kawai, N.Iwadera
The research activities cover (1)the development, evaluation and applicationof dental and biomedical materials, (2)the development of methods and equipments
for fabrication of materials and prostheses and (3)the measurement of properties.
These are concerned with mechanical, thermal properties, corrosion, surface
treatment, biocompatibility, bioreactivity, estheticity and various methods ofimaging and microanalyses. Many researches are related to dental, biological andengineering fields and performed in collaboration with clinical departments
including Removable Prosthetic Dentistry(Prof. Atsuro Yokoyama),
Orthodontics (Prof. Junnichiro Iida), Operative Dentistry(Prof. Hidehiko
Sano), Oral and Maxillofacial Surgery (Prof. Yasunori Totsuka), Crown andBridge Prosthodontics (Prof. Noboru Ohata).
Current topics on research are as follows;

38

CURRENT ACTIVITIES and PRESENTATIONS

CRGHU(1) Biocompatibility and biomedical application of carbon nanotubes(CNT) andother fine particles
Biocompatibility and cytotoxicity of carbon nanotubes(CNT), carbon
nanofibers(CNF), fullerene and other nano materials were investigated. Various
type of CNT including single and muti-wall CNTs(SWCNT, MWCNT) and CNF
were used with the aim of the biomedical application and the pretreatment methodof purification, solubilization, dispersion, surface modification were developed.
Biochemical cell functional test of cell survival rate, LDH activity, emission ofoxygen radicals and cytokines IL-1β, IL-8, TNF-α, M-CSF and implantation test
in soft tissue was done and bioreaction was evaluated. With the decrease ofparticle size the cytotoxicity originated from the physical size effect was
pronounced especially below 10µm. Maany interesting properties advantageous
to buomedical application such as affinity for adhesion of cells,
proteins,saccharides; precipitation of apatite in artificial salivary fluid and strong
binding of psuedopodium grown into the agglomeration of CNTs as scaffold,Applications of the monotubes as delivery system of DNA, protein, saccharic tips
and the sintered bulk as implant materials are also developed.
(2) Development of functionally graded dental implant
The dental implant with the structure of functionally graded materials(FGM) has been fabricated to satisfy different properties. The typical example issuch that the composition changes from the biocompatible metal, Ti, at one end,
increasing the content of ceramics, hydroxyapatite (HAP), principal component ofbone and teeth, toward 100% HAP at the other end. This can control the functionsof mechanical properties and biocompatibility, optimize them, depending on thenecessity of each part of implant, without the abrupt change by the formation of
discrete boundary. The effect of FGM structure Ti/HAP, Ti/Co on tissue response
is investigated by the animal implantation test into rats and rabbits. The tissue
reaction and new bone formation around the implant to the gradient composition isevaluated by both the conventional method using an optical microscope withstained specimens and by elemental mapping and other imaging methods using
electron microprobe analysis(EPMA) and X-ray scanning analytical
microscope(XSAM) with unstained specimens.
(3) Modifications of carbon nanotubes for biological applications

39

CURRENT ACTIVITIES and PRESENTATIONS

CRGHUFor biomedical applications of carbon nanotubes (CNTs), newmodification methods to give bioactivity or biocompatibility are needed forachievement of various required designs. Modification and immobilization ofvarious functional molecules on CNTs by covalent and non-covalent methods were
investigated. Multi-walled carbon nanotubes (MWNTs) coated with acarbohydrate-carrying polymer can be easily prepared by a non-covalent and via
hydrophobic interactions. The carbohydrate coated MWNT was found to acquire aselective binding affinity to the corresponding lectin without a nonspecificinteraction. On the other hand, a bare MWNT interacted nonspecifically withlectins. These results showed that a MWNT coated with a carbohydrate-carrying
polymer has the biological recognition signals. Secondly, we developed abiomimetic coating method to produce the architecture of crystalline apatite at
nano-scale levels on the surface of MWNTs. After immersion of MWNTs inrevised simulated body fluid (r-SBF), the crystallites at nano level were grownradially originating from a common center in the middle of a single MWNT andperpendicularly to the longitudinal direction of MWNT. MWNTs with the definedsurface morphology of nano apatite crystallites could be useful as biomaterials for
scaffolds and for the biomedical applications.
(4) Development of FRP esthetic orthodontic wire
To realize the esthetic, transparent orthodontic wire the FRP wires ofthe diameter 0.5mm with the multiple fiber structure has been fabricated by either
drawing of fiber-polymer complex at 250C or photopolymerization method.
Biocompatible CaO-P2O5-SiO2-Al2O3 (CPSA) glass fibers of 8-20µm in diameterare oriented unidimensionally to the longitudinal direction in polymer matrix of
PMMA, UDMA or bis-GMA. The improvement has been done to obtain theadequate flexural strength and higher torque. FRP wire shows the sufficient
flexural strength and a very good elastic recovery. The dependence of Young's
modulus and flexural stress on fiber fraction obeys very well the rule of mixture.
This FRP wire can cover the range of the strength corresponding to theconventional metal orthodontic wires from Ni-Ti used in the initial stage oforthodontic treatments to Co-Cr used in the last stage by changing the volume ratioof glass fibers with the same external diameter. FRP wire can satisfy bothmechanical properties and estheticity, which is not possible for the conventional

40

CURRENT ACTIVITIES and PRESENTATIONS

CRGHU

metal wire.
(5) Cytotoxicity due to ions and fine particles of Ti and other metals in vivo and invitro:The removal of Ti plates for fixing jaw bone in 6 months after operation
often reveals the slightly dark colored tissue in the circumferential soft tissue. The
observation and analysis by optical microscopy, electron microscopy and XSAM
revealed that the colored tissue contains the abraded fine particles of Ti, probably
produced during plate fixation in operation.
The animal experiments to implant various sizes of Ti particles of
1-100µm and macroscopic cylindrical Ti implant in µm order for 3 days to 8
months showed that the macroscopic size of Ti was encircled with fibrousconnective tissue layer from early stage and there was no inflammation. As thesize of particle becomes smaller, many phagocytic cells appear with fibrousconnective tissue layer inside the particle inserted region and tissue showedinflammation. It takes more time to encircle the particle-contained tissue region
and heal inflammation. For 1-3µm the inserted region is never encircled withfibrous connective tissue layer and inflammation continues.
The in vitro cell functional tests on cell survial rate, LDH(Lactate
Hydrogenase CII) protein released at the breakdown of cell membrane andsuperoxided anion(O2-) sing human neutrophils showed that Ni solution has he cell
disruption effect. The deformed and disrupted morphology of neutrophils was
confirmed by SEM observation. Whilst Ti and V solution showed the increase of
superoxide anion and negligible change in the others, which suggests the cellstimulation effect. SEM observation confirmed that neutrophis are inflated withmore complicated polyacicular morphology. One of the marking cytokines
released at phagocytization, TNF-α, was not detected in any solution of Ni, V, Ti,
the simulated body fluid(Hank's solution) mixed with 10mm paricles of Ti andwith submicron size Ni particles. TNF-α was found only in the 1-3µm Ti particle
mixed Hank's solution, which suggests that particles were phagocytized. SEM
observation and EDS elemental analysis confirmed the phagocytosis of Ti particles
by neutrophils.
The difference of cell reaction to 1-3µm and 10µm Ti particles suggests

41

CURRENT ACTIVITIES and PRESENTATIONSCRGHUthat the particles(1-3µm) smaller than cell size(about 5µm in neutrophils) induces
cytotoxicity as a result of phagocytosis, while for particles larger than cellsize(10µm) phagocytosis is not possible, resulting in the less clear cytotoxicity
effect.
The study shows the cytotoxicity originating from physical size effect ofparticles other than biochemical toxicity effect, which is significant for the cases
where the fine particles are produced during abrasion by long term usage ofmoving parts in the artificial bone joint.
(6) In situ observation of etching process of human teeth in acid agent by atomic
force microscopy
Composite resin with fillers of ceramic powders in polymer matrix has
estheticity similar to natural teeth color and is widely used for treatments of caries
in incisal teeth. Physical-mechanical anchoring effect plays an important part inbinding force between teeth and composite resin. The pretreatment to makeetching of teeth is generally done using acid agents for enhancement of binding.
SEM is usually used for the evaluation of etching effect. It can observe, however,
only the result after a certain etching time. To observe the sequence of etchingprocess it is necessary to prepare the series of specimens treated with different
etching time. Atomic force microscope is applied for the in-situ observation of
etching process of human enamel and dentin in acid agents. The chronologicalchange of surface morphology can be successively observed and quantitative
analysis is done for different etching conditions.
(7) Fabrication of composite resin prostheses by laser lithography:
Laser lithography, one of the CAD/CAM systems to fabricate thepolymer models by piling up the thin slices, which are photo-polymerized byscanning laser beam originally on the shallow depth of liquid epoxy monomer, wasapplied for the fabrication of dental prosthoses of photo-curing composite resin
composed of silica fillers in the matrix of high strength UDMA resin. The fulldental crown could be fabricated using the shape data pre-designed by computerwith high accuracy due to the smaller polymmerization shrinkage than by
conventional methods. Then the functionally graded dental core and post with
gradually changing filler content from 70 to 0% from the head of core abutment

42

CURRENT ACTIVITIES and PRESENTATIONS

CRGHU

toward the apex of post was successfully fabricated. The stress concentration at thepulp root inserted with the conventional dental post has often caused the fracture in
the surrounding dentin by impact force on the tooth crown. The stress relaxation
effect by application of the functionally graded dental post was confirmed bysimulation using the photoelastic method and finite element method(FEM).
(8) Radiation effects on polymer resin :Radiation effects by C+ion, γ-ray from Co60 and electrons on one of themain matrix polymer UDMA(urethane dimethacrylate) for dental composite resin
were investigated with various mechanical tests and spectroscopies. C+ion
radiation induced the large change in the structure sensitive properties ofmechanical properties, Vickers hardness, flexural strength, abrasion resistance andlittle change in the non-structure sensitive properties of spectroscopies, FT-IR,
Raman scattering, Fluorescence, NMR and thermal expansion coefficient. The
results suggest that the mechanism of radiation effect is mostly due to the physicalstructure change such as lattice defects of vacancies, interstitials, depleted zone
rather than the chemical effect of cross-linking by further progress ofpolymmerization of residual monomers.
(9) Evaluation of biocompatibility of refractory metals and their application
Refractory metals of IVA group(Ti, Zr, Hf), VA group(V, Nb, Ta) and
VIIA group(Re) are investigated in their biocompatibility and other bioreactivities.
Animal implantation tests show that the fraction of direct contact of newly formed
bone to implant material without intervening of fibrous connective tissue at theinterface and the amount of new bone vary depending on materials. The
composites of these refractory metals are also made and the comparison and thecomposite effect is investigated.
(10) Surface treatment of dental and biomedical materials with sol-gel method
Biocompatibility and adhesivity to tissue is important for dental
materials. Various dental metals were coated by amorphous silica gels with sol-gel
method. In some cases, biocompatibility were improved.
(11) Tissues and dental materials observation by XSAM43

CURRENT ACTIVITIES and PRESENTATIONS

CRGHUThe scanning X-ray analytical microscope (XSAM) was applied forthe analysis of the soft tissue of rat in which various metals including Fe, Cu, SUS,
V, Co, Ni were implanted. The dissolution of implanted metals and inflammationof tissues were observed by elemental mapping image obtained by XSAM.
(12) Bonding property and cytotoxicity of dental zirconia ceramics (YPSZ)
Yttria partially stabilized zirconia (YPSZ) ceramic is suitable for dental
and medical use because of it's high fracture toughness and chemical durability.
The bonding properties of dental zirconia with various luting cements and surface
treatments are investigating. The cytotoxicity dental zirconia ceramics compared toother dental ceramics was also evaluated.
(13) Abrasion-resistant implant made of refractory metal nitrides and carbides
Surface-nitrided titanium(Ti(-N)) showed high corrosion resistanceand nearly equivalent biocompatibility with Ti in soft and hard tissue in animal
implantation test. Surface durability was evaluated by three static and dynamic
mechanical tests; Vickers hardness test, Martens scratch test and for more practical
viewpoint newly developed abrasion test using ultrasonic dental scaler which isused to remove calculus on teeth in dental clinics. Vickers hardness of Ti(-N)
was 1300, ten times larger than Ti. Martens scratch test showed that the bonding of
nitrided layer with 2µm thickness is coherent to matrix Ti and enough strong.
Abraded volume by ultrasonic scaler was increased with the load in Ti, while notrace was formed in Ti-(N), instead stainless tip of scaler was abraded. The test
showed that abrasion would be negligibly small under the practical conditions of
the load 50g in clinics. Ti-(N) with biocompatibility and surface abrasion
resistance would be suitable as abrasion-resistant implant materials for theapplication to the artificial joint of implant and abuttment part of dental implant.
(14) Development of visible-light responsible photocatalysis and its application
The current photocatalysis of anatase TiO2 mostly works only byultraviolet light. To make applicable for medical use it is necessary to develop thevisible-light reactive photocatalysis. Visible light sesitization was obtained bysurface modification with caions of Au, Ag, Cu, Pt, Pd. Depigmentation withvisible light around 470nm which is used for photopolymerization of composite

44

CURRENT ACTIVITIES and PRESENTATIONS

CRGHUresin restoration in dental clinics could be done with the Ag activated TiO2 incontrast to very little effect in an untreated TiO2. Antibacterial effect was also
confirmed to streptococcus mutans, one of the most popular bacteria for caries.
The application to bleaching of pigmented teeth was developed.
(15) Development of discrimination method of resin-restored teeth
In the health checkup in school mass of patients must be checked in thelimited time. Due to the recent development of estheticity of composite resin it is
now very difficult to recognize the resin-restored teeth and discern resin part fromnatural teeth. Total reflection spectroscopy and fluorescence spectroscopy were
measured and images were taken with reflected light and fluorescence light using
the filters to select the appropriate wave length. In the long wave length region
for more than 600nm the reflectivity of teeth is higher than that of composite resin.
The image formed with filtered light, however, did not show the contrast enough todiscern the resin part from tooth. For less than 400nm both teeth and resin
showed the fluorescence emission with high and comparable intensity. For thelight of 430-450nm teeth emitted higher fluorescence and the relative difference islarger. The images formed with fluorescence light for more than 500nm emitted
by 430-450nm light excitation showed the easily recognized contrast to
discriminate resin from tooth.
(16) Microparticles of biodegradable polymers with controlled structure for drugdelivery system
Single and double emulsification solvent evaporation method is
extensively used for more than two decades for the encapsulation of various
substances form simple pharmaceutical products to proteins and DNA.
Particle formation mechanism is crucial for size distribution, andmorphology, which in turn determine the delivery system behavior during
encapsulation and release.
In order to identify and quantify the main influence parameters that
determine the microparticle performance as drug delivery system, the mechanismof particle formation of biodegradable polyesters: poly(DL-lactide co glycolide)and poly(L-Lactide), was investigated in their single and double emulsion
formulation.

45

CURRENT ACTIVITIES and PRESENTATIONS

CRGHUIn situ optical microscopic investigations showed that the microparticles
are formed by accelerated solvent elimination due to the combined effects of highsolvent volatility and polymer precipitation. The fast shrinkage that accompanies
the solvent elimination has important influence on the particle morphology.
Scanning electron microscopy and laser diffractometry evidenced the presence of athin nanoparticulate layer on the microparticles surface. This layer is formed
during the solvent elimination by the shrinkage-induced fragmentation of the
precipitating polymer. It is reasonable to believe that the encapsulated substancewill accumulate in this layer contributing to the initial burst release.
The inner aqueous phase in the double emulsion formulations has
important influence on the mechanism of particle formation. In this casemicroparticles with different structures are generated. The proportions of
microparticles with different structure are determined mainly by the stirring rate
and the polymer concentration.
During solvent elimination the droplets of inner aqueous phase coalesce
under the precipitating polymer pressure. Due to the incompressibility of the inneraqueous phase, the polymer wall often breaks resulting in holes through which theinner aqueous phase is partly expulsed. Furthermore, after particle hardening theholes will contribute to the encapsulated substances leakage through partitioning
with the external aqueous phase, and to the initial burst release.
Other activities:
Dr. Lu Xiong of Southwest Jiaotong University, China joined to ourlaboratory on October 2009 as the postdoctoral researcher of the Japan Society for
Promotion of Science (JSPS) for the development of nano-structured scaffold for
medical and biochemical applications.
The international collaborations are continued with Institute of Dental
Materials Science, Umea University, SWEDEN (Emerita Prof. Maud BERGMAN)
on application of Ti, ZrO2, amalgum for dentistry, and research on side effects,
with Department of Dental Materials, Chonbuk National University, KOREA(Prof.Tae-Sung BAE) on evaluation of mechanical properties of laser-welded Ti,
dental porcelain, with Institute for Materials Science, Dresden Institute ofTechnology, GERMANY (Prof.W.POMPE) on the biocompatibility evaluation
and application of collagen-hydroxyapatite composites and with Biomaterials

46

CURRENT ACTIVITIES and PRESENTATIONSCRGHULaboratory, Department of Materials Science and Engineering, Tsinghua
University, CHINA (Prof.FZ CUI) on the development and biomedical applicationof nanobiomaterials, University Polytechnica Bucharest, Bucharest, Romania (Dr.
ROSCA Iosif Daniel) on the development of polymer biomaterials.

Presentations
Bioreactivity of nanotubes and nanoparticles, Fumio Watari, 36th meeting of thefullerene nanotube society, Nagoya, Mar. 2009.
Cell culture on carbon nanotubes, Fumio Watari,, Tsukasa Akasaka, Michiko
Terada, Takamitsu Koshikawa, Motohiro Uo, Yoshimasa Kitagawa, 119th meetingof the surface finishing society, Kofu, Mar. 2009.
Bioreactivity of nanoparticles –biointeractive and bioreactive properties, Fumio
Watari, Atsuro Yokoyama, Tsukasa Akasaka, Motohiro Uo, Shigeaki Abe,
Sachiko Ito, Ikuko Oguchi, Yasutaka Yawaka, 31th meeting of Japanesebiomaterials society, Nov. Kyoto, 2009.
Nanomaterials and bioreaction: Invitation to Biomedical, F.Watari, M.Uo,
T.Akasaka, S.Abe, O.Iuko: 9th Asian BioCeramics Symposium (ABC2009), Dec,
Nagoya, 2009.
Carbon nanotubes/collagen composite for biomedical apprications, Uo M. Terada
M., Akasaka T., Kitagawa Y., Watari F.; First International Conference on
Multifunctional, Hybrid and Nanomaterials, Tours, Mar. 2009.
Preparation and properties of dental composite resin cured under near infraredirradiation, Uo M., Kudo E., Okada A., Soga K., Kogo Y.; The 26th International
Conference of Photopolymer Science and Technology, Chiba, June, 2009.

47

CURRENT ACTIVITIES and PRESENTATIONS

CRGHUMicro XAFS analysis of metallic element containing biological specimens using
the polycapillary focusing X-ray optics, Uo M., Asakura K., 14th International
Conference on X-ray Absorption Fine Structure (XAFS14); Camerino, July,2009.
XAFS analysis of corrosion product of Ni-Ti alloy and stainless steel in soft tissue,
Motohiro Uo, Tsukasa Akasaka, Shigeaki Abe, Fumio Watari, 53rd The JapaneseSociety of Dental Materials and Devices, Tokyo, Apl. 2009
XAFS analysis of the corrosion products of Ni-Ti alloy and stainless steel, Uo
Motohiro, Watari Fumio, Asaoka Kenzo, 54th The Japanese Society of Dental
Materials and Devices, Oct. 2009
Rapid analysis of metallic restorations of metal allergy patients, Motohiro Uo,
Fumio Watari, Michiko Terada, Yoshimasa Kitagawa, Akiko Mabuchi, Yasunori
Totsuka, 54th meeting of the Japanese society of oral surgery, Sapporo, Oct. 2009.
XAFS analysis of corrosion products of biomedical metals, Motohiro Uo, Kiyotaka
Asakura, Kenzo Asaoka, Fumio Watari, 12th meeting of XAFS society, Aomori,Sept. 2009.
Capture of Bacteria with Flexible Carbon Nanotubes, Tsukasa Akasaka, Shigeaki Abe,
Motohiro Uo, Fumio Watari, the 53th General Session of the Japanese Society for Dental
Materials and Devices, Tokyo, Apr.11-12, 2009
Capture of Bacteria and Bactericidal Effect using Carbon Nanotubes, Tsukasa Akasaka,
Shigeaki Abe, Motohiro Uo, Fumio Watari, the 54th General Session of the JapaneseSociety for Dental Materials and Devices, Kagoshima, Oct.1-2, 2009
Bactericidal Effect of Carbon Nanotubes/agar Composite Irradiated with NIR Light on
Streptococcus mutans, Tsukasa Akasaka, Makoto Matsuoka, Takeshi Hashimoto, Fumio
Watari, the 3rd International Conference on Science and Technology for Advanced
Ceramics, Yokohama, Jun.16-18, 200948

CURRENT ACTIVITIES and PRESENTATIONSCRGHUControlled mineralization using biomimetic macromolecule; Daisuke Hayashi,
Shigeaki Abe, Tomoki Ishida, Emi Yamatoya, Tsukasa Akasaka, Motohiro Uo,
Fimio Watari, and Tomoya Takada, 21st annual meeting of Society for Organ
Substitution and Regenaration Medicine, Sapporo, Jan. 2009
Reaction dynamics following electron capture of chlorofluorocarbon adsorbed onwater cluster: A direct density functional theory molecular dynamics study; 2009
winter meetings of Japanese Chemical Society, Hokkaido Division, Shigeaki Abe,
Fumio Watari, and Hiroto Tachikawa, Sapporo, Jan. 2009
A direct MD study on graphene-water interaction system; Shigeaki Abe, Yoshinori
Nagoya, Fumio Watari, and Hiroto Tachikawa, 5th International Conference on
Molecular Electronics and Bioelectronics, Miyazaki, March 2009
An ab initio MO study on the structures and electronic states of hydrogen-bonded
O3-H2O complexes; Shigeaki Abe, Tsukasa Akasaka, Motohiro Uo, Fumio Watari,and Hiroto Tachikawa, 53rd The Japanese Society of Dental Materials and Devices,Tokyo, Apl. 2009
Observation of administered micro/nano-materials in mice; 52nd annual meeting ofJapan Society of Microscopy, Mami Mutoh, Shigeaki Abe, Tsukasa Akasaka,
Motohiro Uo, and Fumio Watari, Sendai, May 2009
Reaction dynamics of chlorofluorocarbon on ice: A dynamics DFT study; Shigeaki
Abe, Fumio Watari, and Hiroto Tachikawa, 22nd symposium on chemical kinetics
and dynamics, Omiya, Jun. 2009
Synthesis and charactarization of polyanionic macromolecules with zinccoordinated compound and its application for controlled calcification; Daisuke
Hayashi, Shigeaki Abe, Tomoki Ishida, Emi Yamatoya, Tsukasa Akasaka,
Motohiro Uo, Fumio Watari, and Tomoya Takada, International Symposium of
Photochemistry and Photophysics of Coordinate Compounds, Sapporo July 200949

CURRENT ACTIVITIES and PRESENTATIONSCRGHUA DFT and MD study on the interaction of nanocarbon materials with watermolecules; Shigeaki Abe, Yoshinori Nagoya, Fumio Watari, and Hiroto Tachikawa,4th International Conference on Polymer Batteries and Fuel Cells, Yokohama, Aug.
2009
An ab-initio study on interaction between graphene and water molecules; Shigeaki
Abe, Fumio Watari, and Hiroto Tachikawa, 3rd annual meeting of Japan Society
for Molecular Science, Nagoya, Sep. 2009
Controlled calcification using biomimetic macromolecules with zinc-imidazole
coordinated compound; Shigeaki Abe, Daisuke Hayashi, Emi Yamatoya, Tomoki
Ishida, Tsukasa Akasaka, Motohiro Uo, Fumio Watari, and Tomoya Takada, 59th
Japan society of coodination chemistry symposium, Nagasaki, Sep. 2009
Synthesis of a carbonic anhydrase analogue and its application for controlledcalcification; Emi Yamatoya, Tomoki Ishida, Shigeaki Abe, Ikuko Oguchi,
Tsukasa Akasaka, Motohiro Uo, Fumio Watari, Daisuke Hayashi, and Tomoya
Takada, Kagoshima, 54th The Japanese Society of Dental Materials and Devices,
Oct. 2009
Photophysical characterization of cumarin doped poly (lactic acid) micro particles
and its fabrication for bioimaging; Shigeaki Abe, Iosif D. Rosca, Takayuki Kiba,
Kiyotada Hosokawa, Hirohisa Kobayashi, Satoru Nitobe, Takashi Hirota, Tsukasa
Akasaka, Motohiro Uo, Yoshinori Kuboki, Shin-Ichiro Sato, and Fumio Watari,
11th International Conference on Electronic Spectroscopy and Surface, Nara, Oct.
2009
Observation of internal distribution of micro/nano-sized ceramics and metals
particles in mice; Shigeaki Abe, Nobuki Iwadera, Mami Mutoh, Chika Koyama,
Mitsue Esaki, Tsukasa Akasaka, Motohiro Uo, Manabu Morita,Yoshinori Kuboki,
Koichi Haneda, Yasutaka Yawaka, Fumio Uchida, Tetsu Yonezawa, and Fumio
Watari, 22nd International Symposium on Ceramics in Medicine (Bioceramics22),
Daegu Oct. 200950

CURRENT ACTIVITIES and PRESENTATIONSCRGHUObservation of biodistribution of several micro/nano-particles in mice and its
visualization; Shigeaki Abe, Nobuki Iwadera, Mami Mutoh, Daisuke Hayashi,
Ikuko Oguchi, Tsukasa Akasaka, Motohiro Uo, Fumio Watari, Tomoya Takada,and Tetsu Yonezawa, 30th annual meeting of Japanese Society for Biomaterials,
Kyoto, Nov. 2009
Evaporation dinamics of water molecules on nanocarbon materials: A
DFT and MD study; Shigeaki Abe, Yoshinori Nagoya, Fumio Watari, andHiroto Tachikawa, 22nd International symposium of microprocesses andnanotechnology, Sapporo Nov. 2009
Internal distribution of several nano-magnetic particles in mice; Shigeaki Abe,
Ikuhiro Kida, M. Esaki, Tsukasa Akasaka, Motohiro Uo, Yoshinori Kuboki,
Manabu Morita, Koichi Haneda, Balachandran Jeyadevan, Yoshinori Sato,
Kazuyuki Tohji, and Fumio Watari, 9th Asian BioCeramics Symposium(ABC2009), Nagoya, Dec. 2009
Controlled mineralization using biomimetic macromolecule with an active reaction
center analogue of Carbonic Anhydrase; Shigeaki Abe, Emi Yamatoya, Tomoki
Ishida, Daisuke Hayashi, Ikuko Ohguchi, Tsukasa Akasaka, Motohiro Uo, Fumio
Watari, and Tomoya Takada, 6th Singapore International Chemical Conference,
Singapore, Dec. 2009
Cell adhesion and proliferation on the inner surface of CNT coated 3D scaffold,
E.Hirata, M.Uo, A.Yokoyama, F.Watari, The 53rd General Session of the JapaneseSociety for Dental Materials and Devicess, Tokyo, April.2009
Bone generation using carbon nanohorns –application for CBR method-,T. Kasai,
T. Kanamori, E. Hirata, S. Yamamoto, H. Komatubara, A. Yokoyama, ,118th
Scientific Meeting of Japan Prosthodontic Society, Kyoto,June.2009
Cell adhesion mechanism on inner surface of multi-walled carbon nanotube
coated3D scaffold, E. Hirata, M. Uo, A. Yokoyama, F. Watari, 1st Annual Meeting of
the Nano Biomedical Society, Sapporo, July.200951

CURRENT ACTIVITIES and PRESENTATIONSCRGHUDevelopment of a 3D Collagen Scaffold Coated With Multiwalled Carbon
Nanotubes, E. Hirata, K. Nodasaka, Y. Takita, N. Ushijima, M. Uo, A. Yokoyama, F.
Watari, 31st annual meeting of the Japanese Society for Biomaterials, Kyoto,
November.2009
Strong Adhesion of Saos-2 Cells to Multi-walled Carbon Nanotubes, M. Matsuoka, T.
Akasaka, Y. Totsuka, F. Watari, The Third International Conference on the Science andTechnology for Advanced Ceramics (STAC-3), Yokohama, Jun. 16−18, 2009
The development of reconstruction materials having both high cellular adhesiveness andelectric conductivity, M. Matsuoka, T. Akasaka, Y. Totsuka, F. Watari, The 54th Congressof the Japanese society of Oral and Maxillofacial surgeons, Sapporo, Oct. 10−12, 2009
The effect of CNT on the growth of hepatic cells, Sachiko Itoh, Tsukasa Akasaka,
Yasutaka Yawaka, Fumio Watari; 53rd The Japanese Society of Dental Materials
and Devices, Tokyo, Apl. 2009
Development of scaffolds for cell culture using an almino-silicate nanotubes,
imogolite, Ishikawa Kosuke, Akasaka Tsukasa, Abe Shigeaki, Uo Motohiro,
Watari Fumio, 54th The Japanese Society of Dental Materials and Devices, Oct.
2009
The behavior of hepatic cells to carbon nanotubes, Ito Sachiko, Akasaka Tsukasa,
Yawaka Yasutaka, Watari Fumio, 54th The Japanese Society of Dental Materials
and Devices, Oct. 2009
Comparison of osteoblastic responses to aluminosilicate nanotubesm imogolite,
K.Ishikawa, T.Akasaka, N.Iwadera, S.Abe, M.Uo, M.Kaga, Y.Yawaka, M.Suzuki,
F.Watari; 9th Asian BioCeramics Symposium (ABC2009), Dec, Nagoya, 2009.
Successive observation of phagocytosis-like activity of liver cells for carbon
nanotubes, S.Itoh, T.Taira, Y.Yawaka, F.Watari; 9th Asian BioCeramics
Symposium (ABC2009), Dec, Nagoya, 2009.

52

CURRENT ACTIVITIES and PRESENTATIONS

CRGHUMicrosturucture evaluation of the interface between dental zirconia ceramics andporcelain, Y. Kawai, M. Uo, F. Watari i; 53rd The Japanese Society of Dental
Materials and Devices, Tokyo, Apl. 2009
Application of flake shaped glass filler containing polycarbonate for non-clasp
partial denture, A. Sasaki, M. Uo, K. Iwasaki, S. Abe, T. Akasaka, F. Watari, 54th
The Japanese Society of Dental Materials and Devices, Oct. 2009
Apatite-like compownd formation on the carbon nanotube surface in bodysimulated fluid, Takamitsu Koshikawa, Motohiro Uo, Tsukasa Akasaka, Yoshinori
Kuboki, Fumio Watari; 53rd The Japanese Society of Dental Materials and Devices,Tokyo, Apl. 2009
Apatite-like precipitation upon carbon nanotubes with calcifying solutions undervarious conditions, Koshikawa Takamitsu, Kuboki Yoshinori, Abe Shigeaki,
Akasaka Tsukasa, Uo Motohiro, Watari Fumio, 54th The Japanese Society of
Dental Materials and Devices, Oct. 2009
Culture of osteoblast cells and marrow cells on carbon nanotube scaffold, Kitahara
Hiromi, Kuboki Yosinori, Akasaka Tsukasa, Watari Fumio, Inoue Nobuo, 54th The
Japanese Society of Dental Materials and Devices, Oct. 2009
Preparation and properties of thermoplastic resin based nanocomposites for thedevelopment of FRP orthodontic wires, Yamagata Shuichi, Akasaka Tsukasa, Uo
Motohiro, Iida Junichiro, Watari Fumio, 54th The Japanese Society of Dental
Materials and Devices, Oct. 2009

Facilities and Capabilities
XSAM: HORIBA XGT-2000V, Scanning X-ray analytical microscope forelemental mapping analysis
XRD: Rigaku Multiflwx, X-ray diffractometer (3kVA)
AFM : TopoMetrix TMX2000 Explorer, AFM for dry and wet specimens
NSOM : TopoMetrix Aurora, Near field Scanning Optical Microscope53

CURRENT ACTIVITIES and PRESENTATIONS

CRGHULaser Raman Spectrometer : Dilor Labram, Laser Raman Spectrometer withmapping analysis
ICP : HITACHI P-4010, ICP emission spectrometer for analysis of elements inaquaous solution
FT/IR : Jasco FT/IR-300E, FT/IR spectrometer with microscopic IR measurement
Particle Size Analyzer : Shimadzu SALD-7000, Particle size distribution analysis
with laser scattering
Surface Area Analyzer : Shumadzu, Surface area analysis with gas
absorption/desorption
Universal Testing Machine : INSTRON MODEL 4204, Testing for mechanicalproperties of materials
Laser Welder : ATJ TLL7000, Nd-YAG pulse laser welder with computer
controlled x-y stage
Cold Isostatic Press : Hiikari Koatsu Kiki (10000atm type and 20000atm type):Kobelco, Large volume isostatic press (4000atm)
Vickers Hardness Tester: Shimadzu
Acoustic Emission : Physical Acoustic Corporation
Thermal Gravitometry and Differential Thermal Analysis(TG/DTA) : Rigaku
Denki
Diamond Cutter : Buehler and Struers diamond cutter

54

CURRENT ACTIVITIES and PRESENTATIONSCRGHULABORATORY OF ADVANCED HIGH-TEMPERATUER
MATERIALS
Prof. Dr. S. Ukai
Tel./Fax.: +81-11-706-6355
E-mail:s-ukai@eng.hokudai.ac.jp
Assoc. Prof. Dr. S. Hayashi
Tel.:+81-11-706-6357 Fax.:+81-11-706-7814
E-mail:hayashi@eng.hokudai.ac.jp
Tech. Staff Mr. J. Tanaka
Tel./Fax.: +81-11-706-6818

Students
Y. Kitajima, M. Auchi, T. Narita, B. Leng, Q. Tang, S. Takagi, D. Igarashi,
M. Yamamoto, A. Minami, T. Matsukawa, S. Kasahara, Y. Sugino, H. Noto,
R. Kawano, K. Takezawa, K. Toyota, T. Nii, R. Miyata

The research activities of the laboratory are directed to the development of theadvanced high strengthened ODS alloys, and an understanding of the mechanismof the high temperature corrosion, oxidation of metals such as superalloys,
inter-metallic compounds, iron-based alloys, and steels.
Current topics on research are in the following:(1) Nano-meso structure control of 9Cr-ODS ferritic steels
Nano-meso structure of the 9Cr-ODS ferritic steels can be successfully
controlled by the α−γ phase transformation, and their high-temperature creep
strength is the most superior worldwide in the class of ferritic tubes. This is owing
to existence of the residual ferrite phase within the tempered martensite phase. In
our group, the formation mechanism of the residual ferrite and the origins its
strength are intensively investigated through synthesizing ODS alloys byball-milling and their analyses by means of nano-indentation measurement,

55

CURRENT ACTIVITIES and PRESENTATIONS

CRGHU

differential thermal analysis, high-temperature X-ray diffraction, SEM and TEM
observation.
It was clearly revealed that the ferrite is able to remain over Ac3 pointby pinning of the a-g interface due to nano-size oxide particles; this ferrite is a
non-equilibrium phase, and designated as residual ferrite. This phase is composedof so-called ultrafine grains with size of 500 nm. Therefore, grain refinement
strengthening can be effectively performed in the residual ferrite phase, which is
the real origin for the superior high-temperature strength of the 9Cr-ODS ferritic
steels.
(2) Texture control of 12Cr-ODS ferritic steels
The appropriate cold-rolling and heat-treatment processes are being
investigated for the manufacture of 12Cr-ODS ferritic steels, focusing on the
texture development. A measurement technique by FE-SEM/EBSP (Electron Back
Scattering Pattern) is mainly applied in this study. Cold-rolling of the sheet induces
strong a-fiber texturing composed of {111}〜{001}<110> parallel to the rolling
direction and rolling plane. Recrystallization of the cold-rolled sheet takes place atelevated temperatures beyond 1100°C. The formation mechanism of therecrystallized texture, typically {011}<001>, was investigated; this unique texture
was revealed to exist within shear bands of the cold-rolled structure. This finding
suggests that the recrystallized grains are nucleated during the stage of cold-rolling,
and are selectively grown at temperatures beyond 1100°C.
(3) Development of Ni-based, Co-based and Nb-based ODS superalloys
Basic study for development of the Ni based ODS superalloys is being
conducted. It was found that mechanical alloying (MA) induces nano-crystal
formation of in 50nm size in the Ni-Y2O3 system, and the nano-size grains aremaintained up to 1300℃. Beyond this temperature, recrystallization andgrain-growth takes place due to coarsening of Y2O3 oxide particles. A study formaking extremely fine distributions of oxide particles is being also conducted; theeffective elements for fine oxide particle distribution were discovered and a patentapplication was conducted. In addition, effects of MA on γ’ (Ni3Al) precipitationand growth in the Ni-Al-Y2O3 system and more practical alloys (MA6000) were56

CURRENT ACTIVITIES and PRESENTATIONS

CRGHU

investigated. Co-based ODS alloys was investigated from a viewpoint of finedistribution of oxide particle by addition of particular elements. Development of
Nb-based ODS alloy was started in the system of Nb-50Al, Nb-15Al and Nb-7Al.
(4) Water vapor effects on the high temperature oxidation of Ni-Al based Al2O3
forming alloys
The effects of water vapor on the oxidation of γ'-Ni-25at%Al-Pt alloys
are still being investigated. Water vapor increased the initial oxidation mass gainon the low Pt containing alloys, but no effect was observed on the exclusive Al2O3
forming high Pt containing alloys. For a longer-term oxidation, growth rate of
α-Al2O3 scale was found to decrease with water vapor present. However it was
found that water vapor stabilized metastable Al2O3 for a longer time exposure, andthe metastable Al2O3 grains grew significantly larger with water vapor present.
(5) Phase transformation behavior of Al2O3 scale during high temperatureoxidation
Very thin (~50nm) Fe, Cr, or Ti coating on NiAl or FeAl alloys wasfound to suppress formation of metastable Al2O3, α-Al2O3 scale formed from theinitial stage of oxidation, and the growth rate of coated alloy decreased
significantly. This direct formation of α-Al2O3 scale was explained by the“sympathetic nucleation” of α-Al2O3 scale from the corundum crystal of Fe2O3 orTi2O3. Those elements were also found to accelerate the phase transformation to
α-Al2O3 when the element was coated on pre-formed metastable Al2O3 scale. Ni
was found to retard the phase transformation to α-Al2O3 scale.
(6) Effect of oxygen content on the stability of an Al2O3 scale on Nb(O)-Al-X
alloys
The formation behavior of an Al2O3 scale on Nb(O)-Al-X alloys arebeing investigated. Oxygen content in Nb substrate was changed with the addition
of Re, Mo, and Ta. The formation behavior of an Al2O3 scale on the oxygen
saturated Nb(O)-X was conducted by an Al pack-cementation process. A very thin,well adhesive Al2O3 scale was found to develop on the alloy with higher oxygen
content, but formation of a Nb-aluminide + internal Al2O3 mixture layer wasobserved on the alloy with intermediate oxygen content. Only the Nb-aluminide57

CURRENT ACTIVITIES and PRESENTATIONSCRGHUlayers were formed on the alloy with low oxygen content. Using of oxygen as aalloying element for Nb alloys is now under investigating to develop the Nb(O)based Al2O3 forming alloys.
(7) Effects of impurity elements on the spallation behavior of low-C steel
Scale spallation behavior was investigated on the low-C hot rolled steelswith different contents of P. Oxide scale was easily spalled off on the steels with P,
when the oxidation was conducted above 1150°C. P-rich oxide scale was found at
the scale/steel interface, resulted in the formation of liquid phase at the interface.
This liquid phase was found to penetrate to a FeO scale along the grain boundaries,
causing a separation between an oxide scale and a steel substrate. This separationis considered to be one of the reasons of the oxide scale spallation.
(8) Effect of water vapor on the oxidation of pure-Ni
The effect of water vapor on the oxidation of pure-Ni is being
investigated. Water vapor was found to have little effect on the oxidation masschange of pure-Ni. However, a duplex oxide layer with outer very porous andinner dense NiO was formed when a pure-Ni was oxidized in an atmospheres
containing water vapor. Outer porous layer was found to consist of very fine
powder-like NiO, and it was easily detached from the surface. The formation
mechanism of the powder-like NiO layer is know under investigating.

Presentations
Phase Transformation Behavior of Al2O3 Scale during High Temperature
Oxidation: Y. Kitajima, T. Nishimoto, S. Ukai, S. Hayashi and T. Narita: The
Winter Joint Meeting of Hokkaido Secs. of Jpn. Inst. Metals and Iron and SteelInst. Jpn., Muroran, Jan.,2009
Mechanism of Recrystallization Textured Microstructure Formation in 12Cr-ODS
Ferritic Steels: H. Numata, S. Ukai, S. Hayashi, T. Kaito and S. Ohtsuka: The
Winter Joint Meeting of Hokkaido Secs. of Jpn. Inst. Metals and Iron and SteelInst. Jpn., Muroran, Jan.,200958

CURRENT ACTIVITIES and PRESENTATIONS

CRGHUNanocrystallization of Nb-base ODS alloy by Mechanical Alloying: A. Minami, S.
Ukai and S. Hayashi: The Winter Joint Meeting of Hokkaido Secs. of Jpn. Inst.
Metals and Iron and Steel Inst. Jpn., Muroran, Jan.,2009
Effect of Substrate Elements on the Phase Transformation Behavior of Al2O3 Scaleat High Temperatures: Y. Kitajima, T. Nishimoto, S. Ukai, S. Hayashi and T.
Narita: The Spring Meeting of Jpn. Inst. Metals., Tokyo, Japan, Mar.,2009.
Effect of Water Vapor Atmosphere on High Temperature Oxidation Behavior ofPure Nickel: Y. Kitajima, S. Ukai, S. Hayashi and T. Narita: The Spring Meetingof Jpn. Inst. Metals., Tokyo, Japan, Mar.,2009.
Relationship between Ultrafine Grain Structure and High-Temperature Strength in
9CrODS Ferritic Steels: N. Chikata, S. Ukai, S. Hayashi, T. Kaito and S. Ohtsuka:
The Spring Meeting of Jpn. Inst. Metals., Tokyo, Japan, Mar.,2009.
Oxide Particle Evolution and Dispersion Refinement in Ni-base ODS Superalloy
by Hf Addition: T. Hoshino, S. Ukai and S. Hayashi: The Spring Meeting of Jpn.
Inst. Metals., Tokyo, Japan, Mar.,2009.
Nanocrystallization and Formation of Oxide Particles by Mechanical Alloying in
Nb-base ODS alloy: A. Minami, S. Ukai and S. Hayashi: The Spring Meeting of
Jpn. Inst. Metals., Tokyo, Japan, Mar.,2009.
α→γ Phase Transformation in 9CrODS Ferritic Steels: M. Yamamoto, S. Ukai, S.
Hayashi, T. Kaito and S. Ohtsuka: The Spring Meeting of Jpn. Inst. Metals., Tokyo,
Japan. Mar.,2009.
Formation Behavior of Oxide Particle in Nb-Al System ODS alloy: A. Minami, S.
Ukai, S. Hayashi and N. Sakaguchi: The Summer Joint Meeting of Hokkaido Secs.
of Jpn. Inst. Metals and Iron and Steel Inst. Jpn., Muroran, Jul.,200959CURRENT ACTIVITIES and PRESENTATIONSCRGHUHigh-Strength of Modified Ausform 9CrODS Steels: S.Ukai, M. Yamamoto, N.
Chikata, S. Hayashi, T. Kaito, S. Ohtsuka, T. Azuma and S. Ohsaki: International
Conference on Fusion Reactor Materials, Sapporo, Japan, Sep., 2009.
Reverse Phase Transformation from Ferrite to Austenite in 9CrODS Ferritic Steels:
M. Yamamoto, S. Ukai, S. Hayashi, T. Kaito and S. Ohtsuka: International
Conference on Fusion Reactor Materials, Sapporo, Japan, Sep., 2009.
Effect of Tungsten Addition on Microstructure and High-Temperature strength of
9CrODSFerritic Steel: T. Narita, S. Ukai, S. Ohtsuka and M. Inoue, International
Conference on Fusion Reactor Materials, Sapporo, Japan, Sep., 2009.
Directional Recrystallization of ODS Alloys by Means of Zone Annealing: Y.
Sugino, S. Ukai and S. Hayashi: International Conference on Fusion Reactor
Materials, Sapporo, Japan, Sep., 2009.
Effect of Fe and Ni Doping on the Phase Transformation of Al2O3 Scale: Y.
Kitajima, T. Nishimoto, S. Ukai, S. Hayashi and T. Narita: The Autumn Meetingof Jpn. Inst. Metals, Kyoto, Japan, Sep., 2009.
Short-term Oxidation Behavior of Ni-Al-Pt Ternary Alloy in Atmospheres
Containing Water Vapor: M. Auchi, S. Ukai, S. Hayashi and T. Narita: The
Autumn Meeting of Jpn. Inst. Metals, Kyoto, Japan, Sep., 2009.
Effect of Grain Size on High Temperature Oxidation in Fe-Cr Ferritic Steel: D.
Igarashi, S. Ukai and S. Hayashi: The Autumn Meeting of Jpn. Inst. Metals, Kyoto,
Japan, Sep., 2009.
Effect of element additions on High Temperature Oxidation Resistance of Nb-Al
alloy: S. Takagi, S. Ukai and S. Hayashi: The Autumn Meeting of Jpn. Inst. Metals,
Kyoto, Japan, Sep., 2009.

60

CURRENT ACTIVITIES and PRESENTATIONSCRGHUFormation of Oxide Particle in Nb-Al System ODS alloy: A. Minami, S. Ukai, S.
Hayashi, N. Sakaguchi and S. Miura: The Autumn Meeting of Jpn. Inst. Metals,
Kyoto, Japan, Sep., 2009.
Relationship between High-Temperature Strength and microstructure of 9CrODS
Ferritic Steels: M. Yamamoto, S. Hayashi, S.Ukai, S. Ohtsuka, T. Kaito, T. Azuma
and S. Ohsaki: The Autumn Meeting of Jpn. Inst. Metals, Kyoto, Japan, Sep.,
2009.
Effect of Phosphorus and Sulfur on High Temperature Oxidation Behavior of
Low-Carbon Steels: S. Kasahara, S. Ukai, S. Hayashi, K. Honda, K. Tanaka and K.
Kinoshita: The Autumn Meeting of Jpn. Inst. Metals, Kyoto, Japan, Sep., 2009.
Directional recrystallization in Ni-base ODS alloy: Y. Sugino, S. Ukai and S.
Hayashi: The Autumn Meeting of Jpn. Inst. Metals., Kyoto, Japan, Sep.,2009.
Transient Liquid-Phase (TLP) Bonding of ODS Martensitic Steels: H. Noto, S.
Ukai and S. Hayashi: The Autumn Meeting of Jpn. Inst. Metals, Kyoto, Japan,
Sep., 2009.
High Temperature Carburization of Hastelloy-X alloy in CH4 gas: C. Matsukawa,
S. Ukai, S. Hayashi and H. Yakuwa: The Autumn Meeting of Jpn. Inst. Metals.,
Kyoto, Japan, Sep.,2009.
Rapid Phase Transformation to α-Al2O3 by Deposition of Various Elements on
Al2O3-forming Alloys: Shigenari Hayashi, Yuri Kitajima, Takumi Nishimoto,Toshio Narita and Shigeharu Ukai, European Federation of Corrosion Workshop,
Frankfurt, Germany, Sep. 2009.
Suppression of metastable Al2O3 formation on β-NiAl and FeAl by Various
Elements Deposition: Yuri Kitajima, Shigenari Hayashi, Takumi Nishimoto,Toshio Narita and Shigeharu Ukai, Gordon Research Conference, New London,
USA, July, 2009.

61

CURRENT ACTIVITIES and PRESENTATIONSCRGHUHigh Temperature Oxidation Behavior of Ni-Al-Pt Alloys in Atmospheres
Containing Water Vapor: M. Auchi, S. Hayashi, T. Narita, S. Ukai, Gordon
Research Conference, New London, USA, July, 2009.
Super ODS Steels R&D for Fuel Cladding of Next Generation Nuclear Systems10) Cladding Tube Manufacturing and Summary; S. Ukai, S. Ohnuki, S. Hayashi,
T. Kaito, M. Inoue,A. Kimura, T. Fujisawa, T. Okuda, F. Abe, Int. Conf. on
Advanced Power Plant, Tokyo, Japan, May, 2009.

62

CURRENT ACTIVITIES and PRESENTATIONSCRGHULABORATORY OF INTERFACE OF MATERIALSAND SURFACE
Prof. Dr. T. Yonezawa
Tel.:+81-11-706-7110 Fax.:+81-11-706-7881
E-mail:tetsu@eng.hokudai.ac.jp
Assoc. Prof. Dr. M. Sakairi
Tel.:+81-11-706-7111, Fax.:+81-11-706-7881
E-mail: msakairi@ eng.hokudai.ac.jp
Research Associate Dr. T. Kikuchi
Tel.:+81-11-706-7112, Fax.:+81-11-706-7881
E-mail: kiku@ eng.hokudai.ac.jp

Researchers
Dr. H. Jha, Dr. N. Nishida, Dr. A. Hyono, N. Tsukamoto

Technical Staff
M. Sugawara

Secretariat
M. Muarta

Students
Y. Shishino, M. Zheng, K. Kawai, R. Goto. M. Kinjo, K. Yanada, Y. Wachi,
J. Tatehara, R. Fujita, S. Fujita, T. Murata, H. Hirano, K. Otani, H. Takahashi,
M. Uchida, S. Udagawa, and K. Saito

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CURRENT ACTIVITIES and PRESENTATIONSCRGHUProf. T. Yonezawa took his position as the full professor in thislaboratory in April 2009. Y. Shishino is a D. Sc. candidate originally belonging to
the University of Tokyo and stayed from April 2009 to February 2010 and went
back to the University of Tokyo. Drs. N. Nishida and A. Hyono joined ourlaboratory from April 2009. N. Tsukamoto and M. Sugawara joined to this groupas a researcher and a technical staff from January 2010. M. Sugawara quitted thislaboratory at the end of March 2010. Dr. N. Nishida quitted this laboratory also at
the end of March 2010 and began his academic carrier as a Research Associate of
Chuo University (Tokyo). Dr. T. Kikuchi was appointed as an associate professor
in this division (Research group of Eco-Process) from April 1, 2010.
The research activities of this group are directed to the development of
nanoparticle preparation processes, an understanding of the mechanism of the hightemperature corrosion in super alloys, intermetallic compounds and iron-based
alloys, and to the development of the corrosion resistant alloys and corrosion
protection of steels with a hot dipping method in sea-water front environment. The
research activity is also directed to an understanding of the solidification
mechanism of metals and Alloys.
Dr. H. Jha left Prof Patrik Schmuki's laboratory in university ofErlangen-Nuremberg Erlangen Germany as postdoctoral researcher on May.
Research work of our group directs toward 1) formation of novel of oxide film fordielectric materials, nano-materials, and anticorrosion film by anodizing and otherthin film formation techniques, 2) development of new solution flow typemicro-droplet cell and its application, and 3) establishment of localized corrosion
mechanism of coated steels, titanium and aluminum alloys.
Current topics on research are in the following:(1) Copper Particle Synthesis and Application
Preparation and application of metallic copper fine and nanoparticles arecarried out intensively. From copper oxides (CuO and Cu2O), non-oxidized

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CRGHU

metallic copper nanoparticles are successfully prepared by a chemical reduction
procedure. Thanks to the optimized covering organic polymer materials, copper
particles are not readily oxidized and can be kept in powder form under ambientcondition for several months. We are now able to disperse these particles
independently and prepare Cu particle pastes. These pastes can be used as aconductive paste.
(2) Liquid plasma to form nanomaterials
Chemical reduction process may be the most common preparative
process of nanoparticles, nanorods, as well as nanoplates. However, thepreparation solution/dispersion should contain metal source, stabilizers, as well as
reducing reagents. Especially stabilizers and reducing reagents are often added
large excess amount. On the contrary, energy, such as photo-energy, microwave,
sonification are good candidates for chemical reduction energies for nanoparticle
preparation. We have recently succeeded to prepare metal nanoparticles by
microwave plasma in water. This process is a very rapid and easy process andmetal-to-metal preparation is also possible according to very high energy of plasma.
0-valent metal nanoparticles, alloys, metal oxides, as well as composite metaloxides can be prepared by this plasma process.
(3) In-situ observation of nanomaterials in TEM at high temperature
In order to reveal the detailed structural changes of nanosized materials
at high temperature were revealed by in-situ TEM observation. With a special gas
introducing specimen folder, the sample can be heated up to 1500 °C. With such
equipments, we observe the sintering process of copper nanoparticles or otherparticles, as well as the crystalling process of nanomaterials.
(4) Surface-assisted laser desorption/ionization mass spectroscopy
Mass spectroscopy is one of the most important chemical analyses
especially understanding the structure of the unknown compounds. Matrix-assisted65

CURRENT ACTIVITIES and PRESENTATIONSCRGHU

laser desorption/ionization (MALDI) mass spectroscopy is probably mostimportant MS method in order to understand m/z values of synthetic polymers aswell as biopolymers. This MS method is very easy and UV pulse laser was justirradiated to the mixture of the sample and organic matrix compounds forsoft-ionization of the specimens. However, MALDI-MS method is not suitable forthe mass analyses of organic molecules in relatively low mass range, i.e., m/z <500 because in this mass range, many mass peaks of the fragment ions of theorganic matrix itself. The strength of the peaks of such ions is very strong
compared to the sample ions. In order to overcome such problems, surface-assisted
laser desorption/ionization (SALDI) mass spectroscopy has been intensively
studied recently. Our laboratory provides various metal and inorganic
nanoparticles for that purpose.
(5) Corrosion of Al alloy in model tap water
An influence of K+ and Na+ in model tap water on corrosion behavior ofA3003 was examined by immersion corrosion tests and galvanic corrosion tests.
The immersed corrosion behavior is strongly depends on the buffer ability of thesolutions, however, the kind of cation addition does not clearly affect on
immersion corrosion behavior. The potential fluctuations and current fluctuations
observed in galvanic corrosion tests show good correlation. A coexistence of Na+
and K+ in model tap water acts as corrosion inhibitor, on the other hand single
existence of either ion does not inhibit corrosion of A3003.
(6) High wettability surface formed on Al by anodizng and drying and its corrosion
resistance
The high wettability surface of aluminum was developed by theanodizing and desiccation treatment. The water contact angle of anodized samples
increases with desiccation time, which indicates that desiccation is an effective
method to achieve hydrophobicity of aluminum porous oxide film. The
hydrophobic samples suffer little corrosion during a long period of immersion in66

CURRENT ACTIVITIES and PRESENTATIONS

CRGHU

3.5 mass% NaCl solution. The rest potential in NaCl solution shows an order ofhydrophobic sample, anodized samplem electropolished sample, which accounts
for the corrosion resistance improvement of both anodizing and desiccation
treatment. This can be explained by the interface area between solution and sample
is reduced as the air-valley phenomenon, which may be the reason for the
improved corrosion resistance.
(7) Corrosion behavior of model cut edge face of coated steel
Focusing pulse YAG laser beam irradiation (PRM) was applied to form
area ratio, Sr, controlled model cut-edge on pre painted Zn and Zn- 55 mass% Al
coated steels. A corrosion behavior of formed model cut-edge was investigated by
wet/dry corrosion test. In high Sr of both specimens, red rusts are observed on steel
substrate at model scratch. The dissolution of coated layer starts at the outer rim ofscratched area and progresses into the zinc coating of under the paint of Zn coatedsteel. On the other hand, zinc rich phase of Zn - 55 mass% Al steel preferentiallydissolved. Because of the preferential zinc rich layer dissolution, and formed
longer corrosion area under the paint.
(8) Anodic reaction of titanium in artificial saliva by PRM
The electrochemical behavior of titanium was examined in artificial
saliva by PRM (photon rupture method) and electrochemical methods. Rest
potential is shifted to lower one by NaF addition in artificial saliva. Passive current
increases with NaF addition in Fusayama-Meyre artificial salvia, but not in
Hanks' balanced salt solution. This difference may be resulted from that in pH.
Titanium reapassivates after oxide film removal by laser irradiation in NaF added
simulated artificial saliva. The more NaF is added, the higher peak current density
and amount of charge after laser irradiation become.
(9) Corrosion behavior of A2024 in shape controlled micro-pit
The purpose of this study is to form shape-controlled micro-pit on Al

67

CURRENT ACTIVITIES and PRESENTATIONSCRGHUalloy by laser irradiation and to investigate the influence of shape on localized
corrosion behavior on Al alloy via electrochemical measurement in micro-pit withdifferent aspect ratio. To control laser irradiation time makes it possible tofabricate the artificial micro-pits with different aspect ratio. The aspect ratio of
about 2 is obtained by 120 s laser irradiation. Rest potential at 2.4 ks after the pit
fabrication becomes lower with increasing the aspect ratio of the fabricated pit.
Repassivation ratio at 0.01 s after activation becomes lower with increasing the
aspect ratio.
(10) Examination of corrosion behavior of 13Cr stainless steel in High Clsolutions.
The purpose of this research is corrosion behavior of low C -13%Cr
stainless steel in high Cl- solutions by electrochemical noise technique. A pitting
potential decreases with increasing solutions temperature and the incubation time
for pitting corrosion at constant potential decreases with increasing applied
potential and with aeration of the solution. In single current fluctuation of
non-growing pit, current increase slowly in proportion to 0.5, and decrease rapidly.
An average PSD value at low frequency range and slope at high frequency range
increase with increasing applied potential.
(11) Formation of 3D and layered structure by Sf-MDC
A new method for maskless fabrication of metal micro-rods or structures bysolution flow type droplet cell, Sf-MDC. The developed Sf-MDC micro fabrication
technique was applied to form Cu micro-rods or patterns on resin. To use an inner
capillary tube as a mold during electrodeposition makes it possible to form Cu
micro-rods of about 15 mm length and about 100 µm diameter. The length can becontrolled by the deposition time. The conductivity of formed Cu micro-rods isabout 11.8 x 106 Sm-1. This technique also makes it possible to form both straightmetal structures as well as branched, layered micro-rods and Cu deposit on resin.
This fabrication technique can be applied to form resistance controlled micro wire68

CURRENT ACTIVITIES and PRESENTATIONS

CRGHU

or local surface treatment.
(12) Development local electrochemical analysis technique using Sf-MDC
A solution resistance reduced solution flow type micro-droplet cell withco-axial dual capillary tubes was developed to analyze local electrochemical
behavior. A Pt counter electrode wire with 50 µm in diameter inserted in the inner
capillary tube, successfully reduced solution resistance between the working andcounter electrodes. The electrochemical performance of developed droplet cell isvery similar to that of traditional macro size electrochemical cells. The Sf-MDC
was applied to obtain line profiles of a current at a constant potential forcross-sections of model metal interfaces, and the current changed at the modelinterface of nickel and substrate, the spatial resolution of the developed droplet cell
was reduced with increasing scanning speed of the cell.
(13) Formation of alumina nano-dots by LPD and anodizing
Liquid phase deposition, LPD, is direct oxide film formation techniquefrom solutions. This technique makes it possible to form oxide film or oxide
particle without post heating. Combined process of anodizing and LPD, make itpossible to form oxide nano-dots, which have convex lens like shape. The purposeof this study is to investigate the influence on LPD and anodizing conditions on
structure of formed oxide nano-dots. The nano-dots array can be formed on Al
substrate.
(14) Local Oxide Film Formation on Al with Laser Irradiation and Anodizing in
Ematal BathThe localized formation of porous type oxide film on aluminum byanodizing in Ematal bath, laser irradiation, and re-anodizing is studied. The
pore-sealing of the oxide film gave rise to a considerable improvement of theinsulating properties of the anodic oxide film, showing a potential function similar
to masks in Ematal bath. The oxide film was completely removed from the69

CURRENT ACTIVITIES and PRESENTATIONSCRGHUaluminum substrate by laser irradiation, and grooves with 70 µm width and 15 µm
depth were fabricated. Anodic oxide film grows radially at the laser-irradiated areaby re-anodizing. Formation of oxide film was not observed at areas that were notlaser-irradiated, and this suggests good insulating properties of the pore-sealedoxide film formed by first anodizing.
(15) Effect of stress on oxide film structure and formation rate in model BWR
condition
It is important to clarify role of thin oxide film on SCC in BWR or PWR
environments. The initial oxide film structure and growth rate which were formedin model BWR environment were investigated by Raman spectroscopy,
ellipsemetory and electrochemical impedance spectroscopy. The formed oxide film
was Fe3O4,γ − Fe2O3, Fe-Cr spinel. The formation rate was increased withincreasing applied stress.
Other activities
In May, Assoc. Prof. Sakairi attended 5th Kurt Schwabe Symposium inElectrochemistry held at the University of Erlangen-Nuremberg, Erlangen,Germany and presented paper entitled "Repassivation Behavior of Ti in Hanks
Solution with PRM". After the symposium he visited Faculty of Materials Science
and Ceramics, AGH-University of Science and Technology, Krakow Poland andmeet Prof. Darek Kata and other professors in AGH-University of Science andTechnology.
In September, Assoc. Prof. Sakairi attended Eurocorr 2009 held in Nice,
France and presented paper entitled "Galvanic Corrosion Behavior of 3003
Aluminum Alloy in Model Tap Water."
In October, Assoc. Prof. Sakrairi attended 216th ECS held in Vienna
Austria and presented papers entitled "Effect of surface condition and compositionof solutions on repassivation behavior of titanium by PRM in vitro." and "Wet/Dry
Cycle Corrosion Behavior of Model Cut-Edge Formed on Pre-painted Zinc Alloy70CURRENT ACTIVITIES and PRESENTATIONSCRGHUCoated Steels by Laser Fabrication."
In November Assoc. Prof. Sakrairi attended APGalva held in Jiju, Korea
and presented paper entitled "Model Cut-Edge Formed on Zinc Coated Steels by
Laser Machining and Its Corrosion Behavior."

Presentations
Synthesis and Application of Metal Nanomaterials Prepared in Flasks, Tetsu
Yonezawa: Material Science Meeting, Hokkaido Univ., Sapporo, December 2009
(Invited)
Preparation of Copper Nanoparticles by Microwave Plasma in Lquid, KunihikoMori, Susumu Sato, Osamu Ariyada, Tetsu Yonezawa, Astsushi Hyono, Yoshio
Okano: 3rd symposium of Japan Society of Electromagnetic Wave Energy
Applications, Morito Memorial Hall, Tokyo University of Science, Tokyo,
November 2009.
Cu Nano-/Fine-particles Covered by Polymer Nanoskin: Material for MLCC,
Tetsu Yonezawa: ICAM 2009 (11th International Conference on Advanced Materials),
Rio de Janeiro, Brazil, September 2009 (Invited)
Preparation of Aqueous Dispersion of Metal Nanoparticles and Applications for
Inorganic/Organic Hybrid Resin, Yuichi Shishino, Tetsu Yonezawa, Hiroshi
Nishihara, Kaname Hase, 62nd Annual Meeting of the Division of Colloid andInterface Surface, CSJ, Okayama University of Science, Okayama, September
2009.
Preparation of Extremely Small Metal Nanoparticles and Their Luminescent
Properties, Yuichi Shishino, Tetsu Yonezawa, Koji Kawai, Hiroshi Nishihara, 58th
Symposium of the Society of Polymer Science, Japan, Kumamoto University,71

CURRENT ACTIVITIES and PRESENTATIONSCRGHUKumamoto, September 2009.

Wet Preparation of Metal Nanoparticles and Applications, Tetsu Yonezawa, 2009
Meeting of Mining and Metallurgical Institute of Japan, Hokkaido University,
Sapporo, September 2009 (Invited).
Quantitative Calculation of Interactions of Blood Cells, Atsushi Hyono, Toshio
Matsuda, Hiroyuki Ohshima, Tetsu Yonezawa, Summer Session of Hokkaido
Branch, Chemical Society of Japan, Tomakomai Kosen, Tomakomai, July 2009
Preparation of Gold Nanoparticle-Dispersed Transparent Resin and Its Optical
Property, Yuichi Shishino, Tetsu Yonezawa, Hiroshi Nishihara, Summer Sessionof Hokkaido Branch, Chemical Society of Japan, Tomakomai Kosen, Tomakomai,
July 2009
Effect of F- ions on repassivation of Ti in Hank's, M. Kinjyo, M. Sakairi and T.
Kikuchi, The Winter Joint Meeting of The Hokkaido Secs. of Jpn. Inst. Metals and
ISIJ, Muroran, Jan., 2009.
Formation of model pit on Al and its corrosion behavior, K. Yanada, M. Sakairi
and T. Kikuchi, ibid.
Effect of current on fabrication of Cu structure by Sf-MDC, R. Goto, M. Sakairi
and T. Kikuchi, ibid.
Metal patterning by using Pd catalyst and Laser ablation, Y. Wachi, T. Kikuchi
and M. Sakairi, Winter Joint Meeting The Hokkaido Secs. of Chem. Soc. Jpn. And
Jpn. Soc. Anal. Chem. Sapporo, Jan., 2009.

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Localized Ni patterning by using Pd catalyst and Laser irradiation, Y. Wachi, T.
Kikuchi and M. Sakairi, The 119th Surf. Fin. Soc. Jpn. spring meeting, Yamanashi,
March, 2009.
Formation of micro-Cu rod by modified Sf-MDC, Y. Goto, M. Sakairi and T.
Kikuchi, ibid.
Effect of cation on corrosion of A3003 in model tap watere, M. Sakairi, A. Kaneko,
T. Kikuchi, 144th spring meeting of Jpn. Inst. Metals, Tokyo, March, 2009.
Formation of model cut-edge on pr-coated steel and its corrosion behavior, M.
Sakairi, A. Kageyama and T. Kikuchi, ibid.
Electrochemical behavior of newly developed Sf-MDC, M. Sakairi, T. Murata andT. Kikuchi, The Spring meeting of ISIJ, Tokyo, March, 2009.
Localized dissolution of Fe by Sf-MDC, T. Murata, M. Sakairi and T. Kikuchi,
The 76th Meeting of the Electrochem. Soc. of Jpn., Kofu, March, 2009.
Formation of oxide nano-dots on Al by LPD and anodizing, R. Fujita, M. Sakairi
and T. Kikuchi, ibid.
Effect of PWHT on electrochemical behavior of low C - 13%Cr welded joints byusing solution flow type micro-droplet, S. Hashizume, T. Nakayama, M. Sakairi
and K. Fushimi, Corrosion 2009, Atlanta Grogea, March, 2009.
Fabrication of model pit on A2024 by laser irradiation and its corrosion behavior,
M. Sakairi, K. Yanada and T. Kikuchi, Spring meeting of Light metal soc., May,
Noboribetsu, 2009.
Repassivation kinetics of Ti at repeated irradiation in Hanks solution by PRM, M.

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CURRENT ACTIVITIES and PRESENTATIONS

CRGHUKinjyo, T. Kikuchi and M. Sakairi, Zriryo-to-Kankyo2009, May, Tokyo, 2009.

Fabrication of model pit on 2000 Al alloy by laser irradiation and its corrosion
behavior, K. Yanada, M. Sakairi and T. Kikuchi ibid.
Investigation of effect of initial surface conditions on field crystallization of Al
anodic oxide film with synchrotron X-ray diffraction, M. Sakairi, T. Kikuchi, D.
Nagasawa and T. Suda, ASST2009, Leiden, May, 2009.
Formation of micro-pits on al alloy with PRM and initial stage of localized
corrosion in the formed pits, M. Sakairi, K. Yanada, T. Kikuchi, Y. Oya and Y.
Kojima, ibid.
Repassivation Behavior of Ti in Hanks Solution with PRM, M. Sakairi, M. Kinjyo
and T. Kikuchi, KSCS2009, Erlannge, Germany, June, 2009.
Formation of semi-speher alumina structure by LPD and anodizing, R. Fujita, M.
Sakairi, H. Jha and T. Kikuch, Summer Joint Meeting The Hokkaido Secs. ofChem. Soc. Jpn. And Jpn. Soc. Anal. Chem. Tomakomai, July, 2009.
Micro-fabrication on metal surface by Sf-MDC, T. Murata, M. Sakairi and T.
Kikuchi, ibid.
Electrochemical behavior of stainless steel in acid NaCl solutions, J. Tatehara, M.
Sakairi and T. Kikuchi, ibid.
Galvanic corrosion behavior of 3003 Aluminum alloy in model tap water,
M.Sakairi, A. Kaneko,T. Kikuchi, Y. Seki, and D. Nagasawa, Eurocorr 2009, Nice,
September, Farance, 2009.

74

CURRENT ACTIVITIES and PRESENTATIONSCRGHUElectrochemical mixed process for micro-fabrication of Al, Y. Wachi, T. Kikuchi,
M. Sakairi and T. Yonezawa, The 120th annual meeting of J. Soc. Sarf. Fin.,
Makuhari, September, 2009.
Localized anodizing of aluminum in Ematarl solution, S. Fujita, T. Kikuchi, M.
Sakairi and T. Yonezawa, ibid.
Local metal deposition on resin by new type Sf-MDC, Y. Goto, M. Sakairi and T.
Kikuchi, ibid.
Effect of working distance on micro-fabrication by Sf-MDC, T. Murata, M. Sakairi,
T. Kikuchi and K. Fushimi, The 2009 autumn meeting of the Electrochem. Soc. of
Jpn., Tokyo, September, 2009.
Formation hemisphere alumina dots by LPD and anodizing, R. Fujita, M. Sakairi,
H. Jha and T. Kikuchi, ibid.
Galvanic corrosion of A5000 in model tap water, M. Sakairi, A. Kaneko, T.
Kikuchi, Y. Seki and D. Nagasawa, The 145th autumn meeting of Jpn. Inst. Metal,
Kyoto, September, 2009.
ENA of 13%Cr in acid NaCl solutions, J. Tatehara, M. Sakairi, T. Kikuchi and S.
Hashizume, The 56th Jpn. Conf. on Materials and Environments, Osaka,
September, 2009.
Anodic dissolution of Ti in artificial saliva by PRM, M. Kinjyo, M. Sakairi and T.
Kikuch, ibid.
Changes of restpotensial in model pit formed in Al alloy by PRM, K. Yanada, M.

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Sakairi, T. Kikuchi, Y. Oya and Y. Kojima, ibid.
Wet/Dry Cycle Corrosion Behavior Of Model Cut-Edge Formed On Zinc CoatedSteels By Laser Fabrication, M. Sakairi, A. Kageyama and T. Kikuhci, The 216th
ECS Meeting, Vienna, Austria, October, 2009.
Effect of Surface Condition and Composition of Solutions on Repassivation
Behavior of Titanium by PRM in Vitro, M. Sakairi, M. Kinjyo, H. Miyata and T.
Kikuchi, ibid.
ENA of Galvanic Corrosion of A5052 in Model Tap Water, M. Sakairi, A. Kaneko,
The 117th meeting of Light Metal Soc., Tokyo, November, 2009.
Model Cut-edge Formed on Zinc Coated Steels by Laser Machining and Its
Corrosion Behavior, M. Sakairi, A. Kageyama and T. Kikuchi, APGalva2009,
Cheju, Korea, November, 2009.
Anodic Oxidation of the Inner Wall of the Microchannel Formed by Ti-Al
Reactive Infiltration, M. Ishida, T. Ohmi, M. Sakairi and M. Iguchi, 4th ISEM2009,
Niigata, November, 2009.

Facilities and Capabilities
Transmission Electron Microscopy, Hitachi 300kV
Focused Ion Beam, Hitachi
Field Emission Scanning Electron Microscopy, JEOL
ζ-potential and DLS measurement. Ohtsuka Denshi
Centrifuge: Beckman
Microcentrifuge: TOMY
Ultracentrifuge: Hitachi
Dry Box: Miwa

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CRGHUEvaporator: EYELA
RO Water Purifier: ELGA
Vacuum Drying Oven: YAMATO
Magnetron Sputtering Apparatus: Shinkuu Device
UV Spectrometer: JASCO
IR Spectrometer: Shimadzu
Fluorescence Spectrometer: JASCO
DSC: Rigaku
TG-DTA: Shimadzu
AFM: SII
Atmospheric Plasma in Liquid: ARIOS
AFM: SII SMP AFM with solution cell.
SEM: Hitachi TM-1000
Confocal scanning laser microscope Laser Tech. Co. 1SA-21
Pulse Laser system: 10Hz and 50 Hz pulsed Nd-YAG Laser with electric XYZ
stage
Electrochemical AC Impedance: NF Circuit Design 5095 FRA equipped withpotentiostat.

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CURRENT ACTIVITIES and PRESENTATIONSCRGHUADVANCED COATING LABORATORY
Specially Appointed Professor Dr. Toshio Narita
Tel.:+81-11-706-7208 Fax.:+81-11-706-7208
E-mail:narita@eng.hokudai.ac.jp
Visiting Professor Dr. Masaharu Nakamori
Visiting Associate Professor Dr. Takayuki Yoshioka
Visiting Assistant Professor Dr. Saiko Ohta

Secretary
Ms. Mayumi Ara

Researchers
Dr. S. Konda, Dr. S. Koyama, M. Eng. M. Ohtsuka

Technical Staffs
Mr. T. Tagawa, Ms. M. Sekine, Ms. K. Suetomi, Ms. Y. Oishi, Ms A.
Yoneya, and Ms C. Kawashima

Visiting Researchers
Dr. K. M. Zaini (LIPI, Indonesia)
Dr. T. Izumi (Hitachi Co. Ltd.)
Mr.S. Harashima (Nittobo Co. Ltd.)The Specially Promoted Research (2006-2010) supported by Japanese
Government has been finished by end of March, 2010. A new laboratory wasestablished on advanced coatings, supported by Nittobo Co. Ltd., for term of
three years (2010/07~2012/06), focusing on research and development ofnovel diffusion barrier coating systems to improve high temperaturecapabilities of ultra high temperature materials.

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CURRENT ACTIVITIES and PRESENTATIONSCRGHUThis research projects are aiming to transfer our research successes to thepractical uses, such as gas turbines and jet engines. Current topics on research
are in the following:1) R & D of novel DBC systems to refractory metals such as Nb, Mo, and W.
2) Application of the DBC system to Ni base SC superalloy for land base gas
turbines,
3) Application of the DBC system to Ni-based alloys and Fe-based alloys
4) Understanding high temperature oxidation and corrosion behavior of alloys
and coatings.

Presentations
T.Narita: Creep and oxidation behavior of heat-resistant alloys with diffusion
barrier coating system, The 12th International Conference on Fracture, Ottawa,
Canada, 2009.7.15
T. Narita: The use of diffusion barrier coating system to extend the life of
β-phase and γ’ + γ coatings under cyclic oxidation, Gordon Research
Conference - High Temperature Corrosion, New London, USA, 2009.7.29
T. Narita: Diffusion coating of Hf and Al on Ni-base alloys by co-packing
process, ASEAN-INDIA Workshop and Annual Meeting on Surface
Engineering -2009, Bandung, Indonesia, 2009.12.1

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CRGHUAFFILIATE MEMBERS

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CRGHUAFFILIATE MEMBER
Prof. Dr. Kazuhisa Azumi
TEL/FAX: +81-11-706-6747
Email: azumi@eng.hokudai.ac.jp

Students
Takeshi Sakamoto, Atsushi Naganuma, Jinwei Tang, Jun Kanno, Takayuki Nosaka,
Yuto Aoki, Yusuke Sato, Jungo YajimaPD
Elsentriecy Hassan Hamed
Our group has intended to explore the fundamental corrosion
mechanism of metals, development of corrosion monitoring system, surface
finishing of aluminum and magnesium alloys and corrosion related phenomena infuel cell.
Current topics on research are in the following:(1) Development of a new surface coating method for Mg alloy.
Mg and its alloys are attractive materials because of its light weight,
high strength and bountiful resource. On the other hand high corrosion
susceptibility of them limits their application. Various surface coating techniques
have been, therefore, developed. To clarify the suitable condition forelectrodeposition of corrosion resistive Al coating of Mg, Al was electrodeposited
on a Pt substrate from ionic liquid bath of EMIC containing AlCl3 using various
kind of polarization method including pulse method. Smooth and good adhesive Al
coating was obtained using bipolar current pulse method after optimization of duty
ratio and intensities of anodic and cathodic current.

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CRGHU(2) Corrosion measurement of metals used in saltery plant using multichannel
electrodes method
Saltery plant has been operated under highly corrosive condition, i.e.,aqueous environment containing saturated sodium chloride at high temperature
more than 100 °C. Crevice corrosion is specially severe in this plant even forvery-high corrosion-resistive super stainless steels. Distribution of coupling current
inside and outside of crevice made in various stainless steel specimen was thus
measured using multichannel electrode system in the condition simulating saltery
plant. The specimen constructed from five sheets of SUS316L, NAS64, NAS185N
and NAS254N stainless steels with small holes treated as crevice was immersed insaturated NaCl solution at high temperature up to 100 °C. Distribution of anodic
and cathodic coupling current and its transition in time and space depend on kindof alloy, temperature, and supply of dissolved oxygen, and coverage of the surface
with corrosion product or passive film.
(3) Corrosion monitoring of thin copper film in high temperature solution using
resistometry.
Copper is one of candidate metal for overpack container of radioactive
nuclear wastes produced in atomic power plant to be stored deep-underground to
separate them from civil environment. Temperature-compensated resistometry
method was applied to evaluate corrosion rate of copper in repository condition. A
couple of Cu films with thickness of 5 µm was sealed in laminate film, and one ofthem was exposed to electrolyte solution containing various kinds of ionscontained in underground water kept at 80 °C. Relative resistance change ofcorroded film to non-exposed film was recorded to compensate influence oftemperature change, and corrosion rate of Cu film was evaluate from resistancechange as a function of ion species and dissolved oxygen concentration in thesolution. Corrosion was accelerated in the solution containing sulfide ions orammonium ions, while acceleration of corrosion due to sulfide ions was
suppressed by pre-injected carbonate ions to the solution. Composition and amountof corrosion products was also evaluated from time variation of electrode potential
during the galvanostatic cathodic reduction of corroded specimen and comparedwith the results obtained by resistometry.
(4) Photoelectrochemical property of Zn-Al plating layer on steel

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AFFILIATE MEMBERCRGHUZinc plated steel has been widely used as base material in various
structures. Use of zinc should be, however, reduced because of its limited resource
and thus the performance of corrosion protection property of Zn plating layer
alloyed with other metals such as Al, Mg and Si has been evaluated. In this study
fundamental property of oxide film formed on plating film of ZnAl alloy wasevaluated using electrochemical polarization, photocurrent spectroscopy and
impedance spectroscopy measurements. For example, property of oxide film on
ZnAl alloys altered gradually from an n-type semiconductive film formed on Zn todielectric film formed on Al with increase in Al content in the alloy. Contributionof semiconductive or dielectric property to the oxide film depended on not only
composition of the film but also duration of anodic oxidation and addition of Cl–
ion to the solution.
(5) Fabrication of proton conductive pseudoboehmite thin film
In PEFC system a perfluorosulfonic acid membrane called Nafion®
has been used as a PEM (Proton Exchange Membrane) because of its highly
proton-conductive property provided by a small amount of water contained in the
micro-pore of membrane. Operation temperature of PEFC system is ordinary
limited lower than 100 °C to hold water in the membrane although higher
operation temperature is desirable for better power geneartion efficiency and for
reduction of expensive catalysts. In this work, therefore, proton conductivity
pseudoboehmite thin membrane was fabricated for use as a PEM. Al foil waselectrochemically oxidized to form porous anodic oxide film, immersed in boiled
water to convert the surface of oxide to pseudoboehmite and then the substrate
metal and barrier oxide layer was removed by acidic etching from backside. The
membrane obtained was then deposited with Pt on both sides and built into FC
type cell. This membrane exhibited voltage response to H2 gas supply although thevalue is considerably small.

Presentations

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A. Naganuma, K. Azumi: Application of Multi-channel Electrode System on
Corrosion Research; Corrosion Dream 2009, Electrochemical Society of Japan,
Dec., 2009, Sapporo.
J. Kanno, K. Azumi: Effect of Additives on Ni Electrodeposits, ibid.
K. Azumi , A. Naganuma: Crevice Corrosion Monitoring of Stainless Steel in theEnvironment Simulating Saltely Plant; 56th Annual meeting of Japan Society ofCorrosion Engineering, Sep., 2009, Osaka.
K. Azumi, F. Nishiyama, H. Konno: Fabrication of Optical Fiber pH Sensor using
Porous Anodic Oxide Film of Al; The 120th Annual Meeting of Surf. Finish. Soc.
Jpn., Sep., 2009, Makuhari.
K. Azumi, Y. Tomita, K. Fushimi: Improvement of pH Response of Ir Oxide
electrode; ibid.
K. Azumi: Corrosion Measurement of Metals in Saltely Plant using Multichannel
Electrodes Method; The 21st meeting of research grand by the salt science researchfundation, July, 2009, Tokyo.
K. Azumi, A. Naganuma, T. Nosaka and K. Fushimi: Principle and Application ofMultichannel Electrode System In Corrosion Research; KSCS2009, May, 2009,
Erlangen.
J. Kanno, K. Sakamoto, S. Hayashi, K. Azumi: EBSD Analysis of Additive Effecton Crystallographic Orientation of Ni Plating Layer; 76th Annual Meeting ofElectrochemical Society of Japan, March, 2009, Kyoto.
T. Nosaka, K. Azumi: Size Effect of Al Surface Area on Electroless Ni Plating andZincate Pretreatment; ibid.
A. Naganuma, K. Azumi: Analysis of Corrosion Behavior and Mass Transfer as a
Function of Spatial Orientation and Dimension of Artificial Crevice using

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AFFILIATE MEMBERCRGHUMultichannel Electrode Method; The 119th Annual Meeting of Surf. Finish. Soc.
Jpn., March, 2009, Kofu.
J. Kanno, T. Sakamoto, S. Hayashi and K. Azumi: Analysis of effect of additives
on crystalline orientation of Ni plating by EBSD (Poster); EICCS2009, March,
2009, Sapporo.
A. Naganuma, K. Azumi: Analysis of Corrosion Behavior and Distribution ofChemical Species as a Function of Artificial Crevice Shape using Multichannel
Electrode Method; Winter Joint Meeting The Hokkaido Secs. of Chem. Soc. Jpn.
And Jpn. Soc. Anal. Chem. Sapporo, Jan., 2009, Sapporo.
F. Nishiyama, H. Konno, K. Azumi: Optimization of pH Sensitive Membraneusing Porous Anodic Oxide Film formed on Al; ibid.
J. Kanno, K. Sakaomoto, S. Hayashi, K. Azumi: Effect of Additives on
Crystallographic Orientation of Ni Electroplating Layer using EBSD; ibid.
Y. Tomita, K. Fushimi, K. Azumi: Development of Micro-pH Sensor (Poster);ibid.
T. Nosaka, K. Azumi: Size Effect of Al Surface Area on Zincate Pretreatment(Poster); ibid.

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Prof. Dr. R. O. Suzuki
Tel.:+81-11-706-6339 Fax.:+81-11-706-6342
E-mail:rsuzuki@eng.hokudai.ac.jp

Students
M. Baba, Y. Sasaki, D. Yamada, S. Osaki, K. Watanabe,
K. Otake, N. Kobayashi, T. Takahashi, R. F. A. Descaller,
H. Nashiyama, R. Enmei, I. Ueda and T.Fujisaka

Prof. Ryosuke O. Suzuki merged as the professor of the laboratory of
Eco-processing from Kyoto University on March 2006. He began to study thenon-ferrous metallurgy based on the molten salt electrolysis.
The research activities of the group lead by Prof. Suzuki are directed todesign the economical and environment-friendly processes for materials especiallyat high temperatures. The wide variety of researching approach is introduced suchas molten salt electrolysis, the heat treatment in the ambient pressure of
non-equilibrium gas, thermoelectric phenomenon, etc. The extraction metallurgy of
the refractory metals such as niobium and tantalum, and of valve metals such astitanium, vanadium and zirconium, contains many interesting topics when themolten electrolysis of CaCl2 is applied. The non-equilibrium gases such as ozone
and nitrogen radical are also attractive in the field for oxide and nitride coating.
The thermoelectric power generation is designed from the view of material designand heat exchange between two thermal fluids.
Current topics on corrosion research are in the following:(1) Molten salt electrolysis of CaCl2

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AFFILITE MEMBERCRGHUReduction of the oxides of titanium, vanadium, niobium and tantalum
are studied when the CaO dissolved in the molten CaCl2 is electrochemicallydecomposed to form metallic calcium. A low oxygen potential can form themetallic powders at the cathode. The reduced metallic powder is prepared directlyfrom the oxides as well as CaO. The homogeneous metallic alloy powder can besynthesized from the oxide mixture using the same method. The mechanism of this
proposal is examined from the electrochemistry and thermodynamics using the
evolved gas analysis.
(2) Non-equilibrium gas treatment
Pure nitrogen gas is introduced in the field applying a RF high voltage
and it is successfully discharged. The non-equilibrium gas atmosphere extracted
from the field is highly activated and it plays such as nitrogen radicals or N3 gas. It
reacts with the metallic surfaces to form the corresponding nitrides such as Fe4N,
which does not form in an ambient atmosphere of pure nitrogen.
Other activities(3) Thermoelectric power generation
An optimization of the thermoelectric power generation ismathematically designed to generate the maximum output. The heat exchange
between the two fluids is optimized to give the largest temperature differencealong the large thermoelectric panels.
(4) Copper removal from the iron scrap
Using the analogy with the copper smelting, we plan that the impurity
copper in molten steel will be removed as the copper sulfide when a high sulfur
potential can be applied to the iron scrap.
Prof. R.O. Suzuki was invited at the International conference on
Thermoelectrics (ICT2009) which was held at Freiburg, Germany, May 2009. He

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talked on the fluid dynamic simulation for thermoelectric energy conversion. Prof.
R.O. Suzuki made an invited lecture at Tokyo in April on preparation of vanadium
based hydrogen storage alloys based on the electrolysis at a high temperature. He
was invited as keynote lecturer at the 18th international conference on Processing
and Fabrication of Advanced Materials (PFAM XVIII) at Sendai, Japan. He talked
on the calciothermic reduction using molten CaCl2 and electrolysis to produce thenoble metals such as titanium and tantalum.
The following foreign scientists visited this laboratory: Prof. Geir
Martin Haarberg, Norwegian University of Science and Technology, Trondheim,
Norway. Ms Reyna Famila Descallar joined us from Mindanao State University,
Philippines, as a master student in e3 class.

Presentations
Silent Discharge under Ambient Pressure of Air for Nitrization of Pure Metals, S.
Akiyama, K. Watanabe and R.O. Suzuki: The Winter Joint Meeting of The
Hokkaido Secs. of Jpn. Inst. Metals and Iron and Steel Inst. Jpn., Muroran, Jan.
2009.
Reduction and Synthesis of Biomedical Ti-29Nb-13Ta-4.6Zr alloy by the Molten
Salt Electrolysis of (CaCl2+CaO), S. Osaki, H. Sakai, Y. Oka and R.O. Suzuki:
The Winter Joint Meeting of The Hokkaido Secs. of Jpn. Inst. Metals and Iron andSteel Inst. Jpn., Muroran, Jan. 2009.
Synthesis of vanadium based hydrogen storage alloys, R.O. Suzuki : The 52th
Annual Meeting of Materials Tailoring, Tokyo, Apr. 2009.
Optimal Fluid Conditions on Thermoelectric Power Generation Using
Multi-Panels, Y. Sasaki and R.O. Suzuki: The Summer Joint Meeting of The

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Hokkaido Secs. of Jpn. Inst. Metals and Iron and Steel Inst. Jpn., Muroran, Jul.
2009.
Thermoelectric Properties of Ternary Compounds Zr3Mn4Si6 and TiMnSi2 ; R.O.
Suzuki and H. Kozasa : The Summer Joint Meeting of The Hokkaido Secs. of Jpn.
Inst. Metals and Iron and Steel Inst. Jpn., Muroran, Jul. 2009.
Thermoelectric Properties of Low Conductive Compounds: Zr3Mn4Si6 andTiMnSi2 ; R.O. Suzuki and H. Kozasa : Int. Conf. of Thermoelctrics, Freiburg,
Germany, Jul. 2009.
Optimal Fluid Direction in the Paths among Thermoelectric Multi-Panels ; R.O.
Suzuki and Y. Sasaki : Int. Conf. of Thermoelctrics, Freiburg, Germany, Jul. 2009.
Optimized Flow Path Condition for the Multi-flat Panel Thermoelectric Generation
Systems ; Y. Sasaki and R.O. Suzuki : 6th Annual Meeting of Jpn. Thermoelctric
Soc., Freiburg, Germany, Jul. 2009.
Electrolysis of Titanium Oxides and Experimental Phase Diagram ; K. Kobayashi
and R.O. Suzuki : Annual Meeting of Jpn. Inst. Metals, Kyoto, Sept. 2009.
Crystallization of Desulfuric Slag ; Y. Kusada, R.O. Suzuki and Y. Kashiwaya :Annual Meeting of Iron and Steel Inst. Jpn., Kyoto, Sept. 2009.
Carbon Resourcing by Molten Salt Electrolysis and Reduction of CO2 Gas at High
Temperature ; H. Sakai, K. Ohtake and R.O. Suzuki : 41th Symp. on Molten Salt
Chemistry, Kyoto, Nov. 2009.
Reduction of Titanium Oxide in OS Process and its Reducing Paths ; K. Kobayashi,
Y. Kobayashi and R.O. Suzuki : 41th Symp. on Molten Salt Chemistry, Kyoto,91

AFFILITE MEMBER

CRGHUNov. 2009.

Direct Reduction of Ti-29Nb-13Ta-4.6Zr Alloy by Calciothermic Reduction in the
Molten CaCl2 ; S. Osaki, H. Sakai and R.O. Suzuki : 41th Symp. on Molten Salt
Chemistry, Kyoto, Nov. 2009.
Solubility and Dissolution Behavior of TiCl4 Gas into the Molten CaCl2 ; J.
Hashidume and R.O. Suzuki : 41th Symp. on Molten Salt Chemistry, Kyoto, Nov.
2009.
Direct Reduction of Ti-29Nb-13Ta-4.6Zr Biomedical Alloy from Oxide Mixture in
Molten CaCl2 ; S. Osaki, H. Sakai and R.O. Suzuki : 18th international conference
on Processing and Fabrication of Advanced Materials (PFAM XVIII), Sendai, Dec.
2009.
Direct Metal Production from Oxides by Using Molten Salt Electrolysis of CaO in
CaCl2 ; R.O. Suzuki : 18th international conference on Processing and Fabricationof Advanced Materials (PFAM XVIII), Sendai, Dec. 2009.

Facilities and Capabilities
X-ray diffractmeter: Philips X’Pert Pro. A set for thin film XRD and powder XRD,
and another set for high temperature XRD using Pt heating planer stage or
Al2O3 crucible with RF heating.
Oxygen and Nitrogen Analyzer: LECO TC-600. Inert gas extraction with carbon
crucible and infrared absorption method, 5mass%-0.05 mass ppm. The
previous set was replaced to the most modern.
Sulfur and Carbon Analyzer: LECO CS-600. Carbon and nitrogen are converted to
CO and NO gas by burning in O2 gas with RF heating and they are detected by
the infrared absorption method. 6mass%-0.6 mass ppm. The previous set was

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AFFILITE MEMBERCRGHUreplaced to the most modern.
CO/CO2 Gas Analyzer IR-400: Yokogawa. In the range of 0.1 vol% and 10 vol%.
NO/SO2 Gas Analyzer IR-400: Yokogawa. In the range of 0.1 vol% and 2 vol%.
Constant voltage generators: Takasago Electrics. 4 sets. Max.50V and 20 A.
High voltage amplifier: Takasago Electrics. 100V-8000V.
Ozone gas generators: 2 sets. max 8 vol%O3 gas using O2 gas.
Thermal Analyzers: SII EXSTAR-6000 TG/DTA. With Pt heater up to 1500C. The
previous apparatus was renewed.
Thermal Conductivity Measuring Unit: Kyoto Electrics. Hot disk method at room
temperature.

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CRGHUAFFILIATE MEMBER
Assoc. Prof. Dr. Koji Fushimi
TEL./FAX: +81-11-706-6737
E-mail: kfushimi@eng.hokudai.ac.jp

Students
T. Yamamoto, K. Matsushita, A. Ono, K. Miyamoto, H. Watanabe
The research activities of the laboratory are directed to the materials
surface science and engineering. We are interested in the micro-electrochemistry
for a better understanding of the interfacial phenomena of metal andsemiconductor electrodes in relation to electrochemical devices, corrosion,passivation, and surface finishing.
Current topics on research are as follows:(1)Micro-indentation Test for Depassivation-repassivation of Metal Surfaces
Micro-indentation test of the iron surface in boric-borate solutions was
carried out to investigate the mechano-electrochemistry of depassivation andrepassivation. The indentation could deform the surface either or both elastically or
plastically, and the electrochemical measurement was used to analysis the current
flowing for repassivation following to depassivation. A series of tests were applied
to investigate the dependence of the mechanism and kinetics ofdepassivation-repassivation on the deformation manner, the conductivity and pHof the solution, the hardness of the specimen substrate, and the thickness of thepassive film.
(2) Modification of Flowing-electrolyte Type Micro-droplet-cell
Flowing-electrolyte type micro-droplet-cell (f-MDC) developed for the
micro-electrochemistry was modified to improve the stability of current flowing in
the cell, the facility of the cell fabrication, and the lateral resolution in the scanning

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MDC application. Instead of a coaxial double capillary used in the conventional
f-MDC, a multi-channel capillary, that was composed of an inner channel and six
outer cannels for the supply fresh electrolyte and for the remove used electrolyte,
respectively, was developed and applied to probe the local electrochemical
reactivity on the aluminum alloy and so on. The effect of oxygen dissolving fromthe meniscus between the droplet and specimen surface was also discussed indetail.
(3) Anisotropic corrosion of iron in pH 1 sulphuric acid
Anisotropic corrosion behaviour of a single grain of pure iron in 0.05 mol
dm-3 sulphuric acid (pH 1) was investigated by a simple polarization technique.
Both corrosion potential and corrosion current were found to be dependent on
crystallographic orientation of the iron grain. A high corrosion current flowed on a
grain showing a relatively noble corrosion potential, although both cathodic andanodic Tafel slopes were independent of the orientation. It was shown thatcathodic hydrogen evolution reaction (HER) governed the corrosion reaction on
the iron grain. Covalent bonding of Fe and H and coverage of H on Fe seem toplay important roles in the HER and anisotropic corrosion behaviour of pure iron.
(4) Development of Coaxial Double Ring Microelectrode for the Probe of a
Scanning Electrochemical Microscope
Heating treatment of quartz capillaries with town gas was applied tofabricate the probe electrode of a scanning electrochemical microscope (SECM).
The treatment enabled to coat the electrically conductive carbonaceous layer with athickness of several hundreds nanometers on both inner and outer walls of thequartz substrate. After the suitable coating the wall surfaces with insulating
polymer resin, the capillary tip was polished to obtain the ring electrodes. From themeasurement of the limiting current in the redox mediator, we could confirm thatthe typical diameter of the electrode was less than 1 micrometer. The fabrication
process of the electrode is highly reproducible and is useful to the further
micro-electrochemistry such as SECM.
(5) Carbonaceous Layer Coating on Type-316 Stainless Steel Plate for PEFC
Bipolar Plate

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A simple method to coat the carbonaceous layer on SUS316 stainless steel
plate was developed. The plates were put in an alumina boat with powder ofpetroleum pitch A240F separately and heated at 1073–1273 K under flowing pureargon. By this process, plates were coated with a uniform carbonaceous layer. The
electric-conductivity of the layer and the corrosion resistance were improved by
the increase in the heating temperature and by the pretreatment of the steel platesurface. After the electroplating of nickel, the layer showed a highelectric-conductivity. It was indicated that the inhibition of oxide formation in thelayer plays an important role for the good conductivity as well as corrosion
resistance.
Other Activities
In September, Dr. Koji Fushimi attended to EuroCorr 2009 held in Nicer,
France, and presented the paper entitled “Mass Transfer Controlling Reaction in
Flowing Electrolyte-type Micro-droplet Cell”. In October, Dr. K. Fushimi and Mr.
Takatoshi Yamamoto attended to The 216th Annual Meeting of Electrochemical
Society held in Vienna, Austria, and presented the papers entitled “Anodic
Dissolution of Titanium in Ethylene Glycol Solution Containing Chloride Salt” and“Effect of Cold-rolling on Passive Film on Pure Iron in pH8.4 Borate Buffer
Solution”, respectively. They also visited Johannes Kepler Universität Linz,
Austria, and discussed with Professor Achim W. Hassel.

Presentations (international symposia)
K. Fushimi, S. Yamamoto, H. Habazaki, H. Konno; “Hydrodynamic Effects in
Flowing Electrolyte-type Micro-droplet Cell”, International SymposiumInternational Symposium for Environmental Innovation Driven by Chemistry and
Catalytic Science (EICCS 2009), Mar. 18-19, Sapporo (2009).
T. Yamamoto, K. Fushimi, H. Konno, S. Miura; “Effect of Cold-rolling on
Passivation of Pure Iron in pH8.4 Borate Solution”, International SymposiumInternational Symposium for Environmental Innovation Driven by Chemistry and
Catalytic Science (EICCS 2009), Mar. 18-19, Sapporo (2009).
M. Seo, K. Fushimi, H. Habazaki, and T. Nakayama; “Polarization Behavior of96

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Nickel in Acidic Perchlorate and Acetate Buffer Solutions Containing Small
Amount of Pb2+”, 60th Annual Meeting of the International Society ofElectrochemistry, Aug. 16-21, Beijing, China (2009).
K. Fushimi, S. Yamamoto, H. Habazaki, H. Konno, “Mass Transfer Controlling
Reaction in Flowing Electrolyte-type Micro-droplet Cell”, EuroCorr 2009, Sep.
6-10, Nice, France (2009).
T. Yamamoto, K. Fushimi, H. Konno, “Current Transients from Anodized
Aluminum Surface Using Micro-indentation Test”, The 3rd GCOE International
Symposium Catalysis as the Basis for the Innovation in Materials Science –Beyond
the Horizon of Materials Chemistry–, Sep. 14-15, Sapporo (2009).
K. Fushimi, H. Kondo, H. Konno, “Anodic Dissolution of Titanium in Ethylene
Glycol Solution Containing Chloride Salt”, The 216th Annual Meeting ofElectrochemical Society, Oct. 6-10, Vienna, Austria (2009).
T. Yamamoto, K. Fushimi, S. Miura, H. Konno, “Effect of Cold-rolling on Passive
Film on Pure Iron in pH8.4 Borate Buffer Solution”, The 216th Annual Meeting ofElectrochemical Society, Oct. 6-10, Vienna, Austria (2009).

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ABSTRACTS of PUBLICATIONSCRGHUPassive Oxide Films and Their In-situ Detection
Toshiaki Ohtsuka
Proc. International Conf. on Materials Engineering for Resources (ICMR) 2009,
189 (2009)
The passive oxide film electrochemically formed on iron wasinvestigated by in-situ ellipsometry and Raman spectroscopy. The thickness of thepassive oxide on iron increases with potential under both stationary andnon-stationary conditions. The growth may be followed by the field-assisted ionicmigration mechanism coupled with non-stationary dissolution of ferric ions fromthe oxide. From spectroscopic ellipsometry, a light-absorption edge was estimatedat 2.6 eV, which may be a band gap energy of the semiconducting passive oxide.
When Fe2+ ions exist in the solution, the anodic deposition of FeOOH.H2O takes
place, resulting in formation of an outer hydrous layer a few 10 nm thick. The
Raman spectra of the passive oxide correspond to those of Fe3O4 and γ-Fe2O3.

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CRGHU

In-situ Raman Spectroscopy for the Passive Oxide Film on Iron in
Neutral Borate Solution
Toshiaki Ohtsuka, Kento Taneda
ECS Trans., 16, 125-131 (2009)
In-situ Raman spectra of the passive oxide film in neutral borate solution at
pH 8.4 was measured without any enhancement such as surface enhanced Raman
scattering or resonance Raman scattering. To measure the Raman spectra of thesurface thin film on the electrode, we introduced a confocal collection system toreject the scattering signal from the electrolytes surrounding the surface in front of
the spectrometer. The background signal is still high, and it is more intensive by
100 times than the Raman signal from the passive film. The difference Raman
signal between the surfaces of the passivated iron and the reduced bare iron reveals
a peak at about 670 cm-1. When we measured the passivated iron surface soon after
transfer from the electrolytes to air, we observed another broad and faint peak at
320 cm-1. From these peaks, we assume that the passive oxide film on iron iscomposed of Fe3O4 and γ-Fe2O3

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CRGHU

Self-healing Ability of Conductive Polypyrrole Coating with
Artificial Defect
D. Kowalski, M. Ueda, T. Ohtsuka
ECS Trans, 16 (52), 177-181 (2009)

A bi-layered PPy film consisting of an inner layer doped withkeggin-structure anions of PMo12O403- and HPO42- (PPy-PMo12) and an outer layer
doped with organic anions of dodecyle sulfate (PPy-DoS) exhibited a self-healing
property when coated on steel. When a defect was introduced into the PPy-coatedsteel immersed in 3.5 % NaCl aquesous splution, the potential initially dectreased
and activation of the coated steel occurs. After a few hours, the potential wasrecovered to the passive region, and passivation conyinued for another 20 hours.
Without any damage, the release of PMo12 doped in the inner layer, was inhibitedby the outer PPy layer doped with DoS. When a defect was introduced into the
PPy film, the inner PPy layer released phosphate and molybdate anions to thedamaged zone due to their decomposition via hydrolysis. Both anions work as
passivation inhibitors and helped to repassivate the damaged zone on the steel.

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CRGHU

Ion-Exchange Treatment of Glass Surface in NaNO3 ‐ TlNO3
Molten Salt
Yasushi TABEI, Mikito UEDA, Toshiaki OHTSUKA, Toshiharu YAMASHITAElectrochemistry, 77, 709-712 (2009)
To make functional glasses, ion-exchange treatment of the glass surface wascarried out in TlNO3-NaNO3 molten salt at 673 K and 723 K for various time
periods, and then the Tl ions embedded in the glass were reduced to metallic Tl
nanoparticles by hydrogen gas. The color of the glass containing metallic Tl
nanoparticles changed to brown or black. The Tl nanoparticles were detected by aqualitative TEM analysis. The optical absorption spectra of these treated glasses
showed a peak at about 370 nm. With increases in the temperature of the molten
salt, the band intensity of the absorption is enhanced. The absorption increase may
correspond to larger particle sizes and densities with the increase in temperature.
The Tl nanoparticles with 10-150 nm diameter were observed at neighboring partsof the glass surface by TEM and FE-SEM.

103

ABSTRACTS of PUBLICATIONSCRGHUElectrodeposition of Bi-Sb-Te Alloys By Pulse Electrolysis in
AlCl3-NaCl-KCl Molten Salt
Mikito UEDA, Shoh TSUCHIYA, and Toshiaki OHTSUKA
Electrochemistry, 77, 659-662 (2009)

The Electrodeposition of Sb-Bi-Te alloy in AlCl3–NaCl–KCl molten salt
containing SbCl3, BiCl3, and TeCl4 at 423K was carried out under constantpotential control and potential pulse control in the melt. The electrodeposition
results show that the SbCl3 concentration is effective to control the composition of
Bi-Sb-Te ternary alloy. The electrodeposited Bi0.5Sb1.5Te3 by pulse electrolysis
with frequency = 100 Hz and D.R.(Duty Ratio) = 75 %, had good crystallinity andthe preferential orientation of the electrodeposit was the (110) plane in thiselectrodeposition experiments. The electrodeposit had homogeneous disk-likegranules. The power factor of the electrodeposit was calculated as 3 x 10-5
Wm-1K-2 from the Seebeck coefficient and the electrical conductivity.

104

ABSTRACTS of PUBLICATIONSCRGHUElectrorefining Reaction of Sodium in Propylene Carbonate
Containing NaPF6
Mikito Ueda, Hideki Hayashi, and Toshiaki Ohtsuka
J. Japan. Inst. Metals, 73, 691-694(2009)

To develop a sodium electrorefining process for the recycling of usedsodium-sulfur secondary battery, a non-aqueous electrolytic melt was investigatedto pursue an efficient solvent and electrolyte for the process. Propylene carbonate
containing NaPF6 was selected, since it has a wide potential window forelectrochemical stability and a weak reactivity with metallic sodium. From theimpedance measurement of propylene carbonate containing NaPF6, the maximum
electric conductivity of 75 mS cm-1 was found at concentration of 1 M NaPF6 at
338 K. The cathodic deposition of metallic sodium on a glassy carbon electrodeand the anodic dissolution of metallic sodium occurred in the electrolytic melt.
Sodium and a small amount of phosphorus were detected in the electrodeposit by
ICP-AES analysis. (Japanese)

105

ABSTRACTS of PUBLICATIONSCRGHURemoving of Mg in Al-Mg Alloy by Calcined Powder from
Used Dry-cell Batteries
Mikito Ueda, Yasutaka Ta, Toshiaki Ohstuka, and Hidenori Takahashi
J. Japan. Inst. Metals, 73, 773-777(2009)

To reduce Mg content in Al-Mg alloy for aluminum recycling, calcined
powder made from used dry-cell battery was reacted with the liquid aluminum alloy.
The powder was found to consist of ZnMn2O4, MnO, ZnO, and carbon by XRD
analysis. After the reaction between pellets of the powder and the alloy in liquid at
973K or 1073K for 3.6×103s, Mg content in the alloy decreased from 4.0 to 2.3
mass%. And at the same time, contents of Mn and Zn in the alloy increased from 0
to about 0.2 and 0.1 mass%, respectively. During the reaction, metallic Mg in theliquid Al-Mg alloy was found to move in to the pellets to form MgO. It may be
assumed that an exchange reaction between Zn2+ at ZnO in the pellets and Mg2+
from the liquid alloy takes place. (Japanese)

106

ABSTRACTS of PUBLICATIONSCRGHUPhotoluminescence from Passive Oxide Films on Nickel and
Chromium by Photo-excitation of UV Light
Yusuke Mito, Mikito Ueda, and Toshiaki Ohtsuka
Corrosion Science, 51, 1540-44 (2009)

Photo-luminescence emission was measured from the thin passive oxide
film on nickel and chromium under the in-situ condition in 0.1 kmol m-3 (M)sulfuric acid solution at pH 0.9 and neutral buffer solution of borate-boric acidmixture at pH 8.4 in order to obtain the insight of the electronic properties in thepassive oxide film as thin as a few nm. The photo-luminescence induced by UV
laser beam at 325 nm wavelength from nickel oxidized in both pH 0.9 sulfuric acidand pH 8.4 borate buffer solutions exhibited a broad spectrum feature with a peakat 400-420nm. The energy of the peak wavelength from 400 to 420nm is2.95-3.10eV which may correspond to the bandgap energy of the semiconduncting
NiO. The photo-luminescence spectra from chromium oxidized in the sulfuric acidand neutral borate solutions had a peak at 400 nm and about 440 nm, respectively.
This photo-emission from nickel and chromium oxidized is assumed to correspondto luminescence accompanied by recombination between excess electrons
produced by UV light illumination in the conduction band and positive holes in thevalence band. The broad tailing of the luminescence at longer wavelength side may
represent high density of localized states originated in an amorphous nature of thepassive oxides.

107

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CRGHUEffect of Oxide Film on Oxygen Reduction Current for The
Platinum-cobalt Alloy Electrode in PEFC
Yuichi Tamura, Kento Taneda, Mikito Ueda, Toshiaki Ohtsuka
Corrosion Science, 51, 1560-64 (2009)

Effect of surface oxide on Pt-Co alloy electrodes on the oxygen
reduction reaction (ORR) was investigated in 0.5 M sulfuric acid solution byelectrochemistry, ellipsometry, laser Raman scattering spectroscopy, and XPS. The
oxide as thick as 1-2 nm increases the overpotential of ORR and falls down
efficiency of PEFC. The thickness of the oxide films is precisely determined byellipsometry. The oxide film 1.9 nm thick was formed on Pt-50 mol % Co
electrode by constant potential oxidation at 1.20 V and the film 1.5 nm thickremains on the electrode at 0.6 V at which ORR already starts. The remainingoxide decreases the current density of ORR and increases the overpotential. On
pure platinum electrode, the similar influence of the oxide film was observed.

108

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CRGHUDepth Profile Analysis of Thin Passive Films on Stainless Steel by
Glow Discharge Optical Emission Spectroscopy
M. Uemura, T. Yamamoto, K. Fushimi, Y. Aoki, K. Shimizu, H. Habazaki
Corrosion Science, 51, 1554-1559 (2009)

Thin passive films formed on highly corrosion-resistant type-312L
stainless steel, containing 20 mass% chromium and 6 mass% molybdenum, in 2
mol dm-3 HCl solution at 293 K have been analyzed by glow discharge opticalemission spectroscopy (GDOES). The stainless steel does not suffer pitting
corrosion even in this aggressive solution, showing a wide passive potential region.
The depth profiles obtained clearly show a two-layer structure of the air-formed
and passive films: an outer iron-rich layer and an inner layer highly enriched inchromium. Alloy-constituting molybdenum is deficient in the inner layer of thepassive films and is enriched in the outer layer, particularly at the active
dissolution potential. The molybdenum species in the outer layer may retard theactive dissolution of stainless steel, promoting the formation of stable passive films
highly enriched in chromium. Chloride ions are present only at the outermost partof the passive films, not penetrating into the interior part.

109

ABSTRACTS of PUBLICATIONSCRGHUFormation of Porous Niobium Films by Oblique Angle Deposition:
Influence of Substrate Morphology
M. Tauseef Tanvir, Y. Aoki and H. HabazakiThin Solid Films, 517, 6711-6716 (2009)

The present work demonstrates the formation of porous niobium films
with separated columnar structures by oblique angle magnetron sputtering forcapacitor application. The niobium films deposited on textured aluminium
substrates, which had concave cell structures with the cell sizes ranging from
125 nm to 550 nm, consist of isolated columns of niobium with wider gaps
between columns developing on the substrates with larger cell sizes. The surface
areas of the deposited films, evaluated by the capacitance of the anodic films
formed at several voltages, increased with an increase in the cell size of substrate.
The surface area decreases with an increase in the formation potential of anodic
films from 2 V to 10 V vs Ag/AgCl, because the gaps are filled with anodic oxide
as a consequence of the large Pilling–Bedworth ratio of 2.6 for the Nb/Nb2O5
system. The reduction of the surface area is suppressed when the substrate withlarger cell size is used, due to the formation of niobium columns with wider gaps,
which are not filled with anodic oxide. The high surface area even at higher
formation voltages of the anodic films is a requisite for capacitor application.

110

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CRGHUImproved Electrical Properties of Silicon-incorporated Anodic
Niobium Oxide Formed on Porous Nb-Si Substrate
M. T. Tanvir, Y. Aoki and H. Habazaki
Applied Surface Science, 255, 8383-8389 (2009)
In the present study, porous Nb–Si alloy films with isolated
nano-column morphology have been successfully developed by oblique angle
magnetron sputtering on to aluminum substrate with concave cell structure. The
deposited films are amorphous with the 15 at% silicon supersaturated into niobium.
The porous Nb-15 at% Si films, as well as niobium films with similar morphology,
are anodized at several voltages up to 50 V in 0.1 mol dm−3 ammonium
pentaborate electrolyte. Due to the presence of sufficient gaps between
neighboring columns, the gaps are not filled with anodic oxide, despite the large
Pilling–Bedworth ratio (for instance, 2.6 for Nb/Nb2O5) and hence, a linear
correlation between the reciprocal of capacitance and formation voltage is obtained
for the Nb-15 at% Si. From the comparison with the anodic films formed on
porous niobium films, it has been found that silicon addition improves the thermal
stability of anodic niobium oxide; the change in capacitance and increase inleakage current become small for the Nb–Si. The findings indicate the potential of
oblique angle deposition to tailor porous non-equilibrium niobium alloy films forhigh performance niobium-base capacitor.

111

ABSTRACTS of PUBLICATIONSCRGHUAnodic Behavior of Nickel in Acidic Perchlorate Solution
Containing Pb2+
M. Seo, N. Kikuchi, K. Fushimi, H. Habazaki, T. Narita and T. Nakayama
ECS Transactions, 16, 109-116 (2009)
The anodic behavior of nickel has been investigated in deaerated acidic
perchlorate solution containing 10-4 M Pb2+ at room temperature. The addition of
Pb2+ in solution shifted the corrosion potential or the potential of anodic current
peak to the more noble direction and suppressed the anodic dissolution of nickel.
The Tafel slope of anodic dissolution decreased from 37 mV decade-1 to 13 mV
decade-1 due to the addition of Pb2+. The uderpotential deposition (UPD) of Pb on
nickel was discussed with relation to the effect of Pb2+ on anodic behavior ofnickel.

112

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CRGHUEffect of Sulfuric Acid on Pit Propagation Behaviour of Aluminium
under AC Etch Process
S. Ono and H. Habazaki
Corrosion Science, 51, 2364-2370 (2009)

Pit propagation on high purity aluminium electrode in 2M HCl solutions
with and without H2SO4 under an alternating current (AC) has been examined. Pit
development and potential transients were dependent on the H2SO4 concentration.
In the sulfate-free etchant, most pits developed from the pretreated surface, withlittle tendency to form clusters of pits. With increasing H2SO4 concentration thesize of the pit clusters increased. There is an optimal H2SO4 concentration, which
is 0.01M H2SO4 in this study, to form a deep etched layer of uniform thickness
with high surface area. At H2SO4 concentrations higher than 0.01M, the pit
propagation proceeded on limited foil surface sites and deep etched regions wereformed locally, since sulfate ions assisted passivation and reduced the number of
pit nucleation sites on foil surface. Analysis of potential transients during theanodic half-cycle supports the hypothesis that sulfate ions retarded the pit
nucleation.

113

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CRGHUPreparation of Self-organized Porous Anodic Niobium Oxide
Microcones and Their Surface Wettability
Y. Oikawa, T. Minami, H. Mayama, K. Tsujii, K. Fushimi, Y. Aoki, P. Skeldon, G.
E. Thompson, H. Habazaki
Acta Materialia, 57, 3941-3946 (2009)
Porous anodic niobium oxide with a pore size of ~10 nm was formed at
10 V in glycerol electrolyte containing 0.6 mol dm-3 K2HPO4 and 0.2 mol dm-3
K3PO4 at 433 K. After prolonged anodizing for 5.4 ks, niobium oxide microcones
develop on the surface. X-ray diffraction patterns of the anodized specimens
revealed that the initially formed anodic oxide is amorphous, but anamorphous-to-crystalline transition occurs during anodizing. As a consequence ofthe preferential chemical dissolution of the initially formed amorphous oxide, due
to different solubility of the amorphous and crystalline oxides, crystalline oxide
microcones appear on the film surface after prolonged anodizing. The surface issuperhydrophilic. After coating with fluorinated alkylsilane, the surface becomessuperhydrophobic with a contact angle of 158° for water. The surface is also oilrepellent, with a contact angle as high as 140° for salad oil.

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CRGHU

Spark Anodizing Behaviour of Titanium and Its Alloys in Alkaline
Aluminate Electrolyte
M. Nakajima, Y. Miura, K. Fushimi and H. Habazaki
Corrosion Science, 51, 1534-1539 (2009)
Spark anodizing of titanium, Ti-6Al-4V and Ti-15V-3Al-3Cr-3Sn inalkaline aluminate electrolyte produces highly crystalline anodic films consisting
mainly of Al2TiO5 with α- and γ-Al2O3 as minor oxide phases, irrespective of
substrate composition. However, the apparent efficiency for film formation
decreases in the following order: Ti-6Al-4V, titanium and Ti-15V-3Al-3Cr-3Sn. A
large amount of aluminium species are incorporated from the electrolyte, probably
by plasma-chemical reaction, and become distributed throughout the film thickness.
This distribution indicates that the electrolyte penetrates near to the film/substrateinterface through the discharge channels. Thus, the outwardly migratingaluminium ions under a high electric field can be present even in the inner part of
the anodic films. Voids are developed at the film/substrate interface, particularlyon the vanadium-containing alloys, reducing the adhesion of the anodic film to thesubstrate.

115

ABSTRACTS of PUBLICATIONSCRGHUThe Influence of Thermal Treatment on The Electronic Properties
of a-Nb2O5
F. La Mantia, M. Santamaria, H. Habazaki and F. Di Quarto
ECS Transactions, 19, 411-422 (2009)
The effect of thermal treatment for 1h at 250°C in air or under vacuumon the electronic structure of thick amorphous anodic niobia was characterized byelectrochemical impedance, differential admittance (DA) and photocurrent
spectroscopy (PCS). The analysis of anodized niobia has revealed that it behaves
as a pure dielectric. The thermal treatment in air increases the value of itsdifferential capacitance. The effect is stronger when the thermal treatment iscarried out in vacuum, and can be cancelled by reanodizing the oxide to its initialformation potential. The frequency dependence of the sample treated in vacuum
exhibited behavior typical of a semiconducting amorphous material. PCS
measurements were used to derive the optical band gap value and to confirm thelocation of the flat band potential that was derived from admittance data.

116

ABSTRACTS of PUBLICATIONSCRGHUCharacterization of Amorphous Anodic Nb2O5 Nanofilm for Gas
Sensing
D. Kowalski, Y. Aoki, H. Habazaki
ECS Transactions, 16, 57-65 (2009)
Amorphous Nb2O5 film of 167 nm thickness was fabricated by anodic
oxidn. of sputter deposited niobium and characterized by TEM, GD-OES and
AFM. The electric properties of the anodic films with sputter-deposited circulargold electrodes were studied by AC impedance spectroscopy in ambient gas
atmospheres of air, argon, oxygen or hydrogen in the temp. range of 25 - 200°C.
The amorphous Nb2O5 showed the character of n-type semiconductor. The cond.
of the film, following the Arrhenius behavior, was independent of the oxygen
partial pressure, but was largely dependent on hydrogen partial pressure. The
conductivity of the Nb2O5 film at room temperature in dry hydrogen was 2.2 ordersof magnitude as high as that in air. The enhanced cond. could be associated withpartial reduction of Nb5+ in dry hydrogen atmosphere. The addition of water
vapor to hydrogen atm. reduced conductivity probably due to suppressing the
reduction of Nb2O5.

117

ABSTRACTS of PUBLICATIONSCRGHUHigh Proton Conductivity in Anodic ZrO2/WO3 Nanofilms
D. Kowalski, Y. Aoki and H. Habazaki
Angewandte Chemie-International Edition, 48, 7582-7585 (2009)
Amorphous double-oxide nanofilm (ZrO2/WO3) is a new class ofproton-conducting electrolyte that can be simply fabricated by physical vapor
deposition (PVD) and anodic oxidation of Zr/W alloy film. The practicalarea-specific resistivity of 0.2 Ω cm2 is reached at a temperature as low as 100 °C
for a 60 nm thick oxide film.

118

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CRGHUImportance of Water Content in Formation of Porous Anodic
Niobium Oxide Films in Hot Phosphate-glycerol Electrolyte
H. Habazaki, Y. Oikawa, K. Fushimi, Y. Aoki, K. Shimizu,
P. Skeldon, G. E. Thompson
Electrochimica Acta, 54, 946-951 (2009)
Niobium has been anodized at a constant current density to 10 V with acurrent decay in 0.8 mol dm-3 K2HPO4-glycerol electrolyte containing 0.08-0.65
mass% water at 433 K to develop porous anodic oxide films. The film growth rate
is markedly increased when the water content is reduced to 0.08 mass%; a 28
µm-thick porous film is developed in this electrolyte by anodizing for 3.6 ks, while
the thickness is 4.6 and 2.6 µm in the electrolytes containing 0.16 and 0.65 mass%water respectively. For all the electrolytes, the film thickness changes
approximately linearly with the charge passed during anodizing, indicating thatchemical dissolution of the developing oxide is negligible. SIMS depth profiling
analysis was carried for anodic films formed in electrolyte containing ~0.4 mass%water with and without enrichment of H218O. Findings disclose that water in theelectrolyte is a predominant source of oxygen in the anodic oxide films. The
anodic films formed in the electrolyte containing 0.65 mass% water are practically
free from phosphorus species. Reduction in water content increased theincorporation of phosphorus species.

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CRGHU

Optimized Observation of Tungsten Tracers for Investigation ofFormation of Porous Anodic Alumina
S. J. Garcia-Vergara, D. Le Clere, T. Hashimoto, H. Habazaki,
P. Skeldon, G. E. Thompson
Electrochimica Acta, 54, 6403-6411 (2009)
Improved methods are presented for investigating the flow of anodic
alumina during the formation of porous anodic films on aluminium in phosphoricacid. In particular, the use of tungsten nanolayer tracers with increased flatness isshown to result in enhanced definition of the influences of flow on the tracer
distribution, as observed by electron microscopy. Additionally, taper sectioning offilms, by ultramicrotomy, and parallel sectioning of films, by sputtering using an
Ar+ ion plasma, enable tungsten distributions across cells to be determined. In thecase of an Al-3.5 at.% W alloy, the flow results in an inner alumina layer lining thepore walls that is relatively free of tungsten species and an outer cell layer ofcomparatively high tungsten content. Both sectioning procedures also show thepresence of fine cell boundary bands of relatively high tungsten content, which aresuggested to result from the transport of tungsten, enriched in the alloy
immediately beneath the film, toward the cell boundary by the alloy/film interface.

120

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CRGHU

Growth of Porous Anodic Films on Sputtering-deposited
Aluminium Incorporating Al-Hf Alloy Nanolayers
S. J. Garcia-Vergara, T. Hashimoto, P. Skeldon, G. E. Thompson, H. HabazakiElectrochimica Acta, 54, 3662-3670 (2009)
Formation of porous anodic films on sputtering-deposited aluminium
incorporating Al-Hf tracer layers has been examined at constant current insulphuric and phosphoric acids. Hafnium was selected as the tracer species since
the migration rates of Hf4+ and Al3+ ions are similar in barrier-type anodic alumina.
The distribution of hafnium in the films was determined using ion beam analysis,
scanning electron microscopy and transmission electron microscopy. Increases in
the anodizing voltage and barrier layer thickness accompany the oxidation ofhafnium and the migration of Hf4+ ions through the barrier layer region of theporous film. Hf4+ and Al3+ ions that migrate to the pore bases are lost to theelectrolyte. Other Hf4+ ions are incorporated into the cell walls. For films formed inphosphoric acid, with relatively thick barrier layers, channelling of the ion current
leads to accelerated outward transport of Hf4+ ions toward the pore base, while a
U-shaped inner edge of the hafnium distribution beneath the pores is associatedwith more slowly transported hafnium species. The tracer behaviours for films
formed in both acids are consistent with the transport of Hf4+ ions in the barrier
layer regions by a combination of flow of film material and ion migration, the flow
being a key factor in the development of the pores. The percentage losses of Hf4+
and Al3+ ions from the films to the electrolyte are relatively Similar, correlatingwith their similar migration rates, and contrast with the retention in the film ofslow migrating W6+ ions, found previously, due to a more dominant role of flow.

121

ABSTRACTS of PUBLICATIONSCRGHUFormation of Porous Aluminum Films with Isolated Columnar
Structure using Physical Vapor Deposition for Medium-voltage
and High-voltage Capacitors
T. Fujii, Y. Aoki, K. Fushimi, T. Makino, S. Ono, H. Habazaki
J. Surf. Finish. Soc. Jpn., 60, 166-169 (2009)
An attempt was made to tailor porous aluminum films with an isolated
columnar structure by magnetron sputtering for potential application to
medium-voltage and high-voltage electrolytic capacitors. The aluminum film wasdeposited at a relatively high Ar pressure of 3.3 Pa on rough aluminum substratewith a cellular texture. Shadowing effects, which were enhanced by the random
incident angle of aluminum atoms at the high Ar pressure and the use of a roughsubstrate, produced the isolated columnar structure of the deposited
film. However, gaps separating neighboring columns were not high enough tomaintain high surface roughness after anodic oxide formation, due to the large
Pilling-Bedworth ratio for the Al/Al2O3 system. The gaps became filler withanodic oxide during anodic film formation. Slight alkaline etching of thedeposited film the increased the gaps such that high surface area was maintained tohigh formation voltages.

122

ABSTRACTS of PUBLICATIONSCRGHUFormation of Anodic films on Sputtering-deposited Al-Hf Alloys
M. Fogazza, M. Santamaria, F. Di Quarto, S. J. Garcia-Vergara, I. Molchan, P.
Skeldon, G. E. Thompson, H. HabazakiElectrochimica Acta, 54, 1070-1075 (2009)
The growth of barrier-type anodic films at high efficiency on a range of
sputtering-deposited Al-Hf alloys, containing from 1 to 95 at.% Hf, has been
investigated in ammonium pentaborate electrolyte. The alloys encompassed
nanocrystalline and amorphous structures, the latter being produced for alloys
containing from 26 to 61 at.% Hf. Except at the highest hafnium content, the films
were amorphous and contained units of HfO2 and Al2O3 distributed relatively
uniformly through the film thickness. Boron species were confined to outer regionsof the films. The boron distributions suggest that the cation transport number
decreases progressively with increasing hafnium concentration in the films, from
~0.4 in anodic alumina to ~0.2 for a film on an Al-61 at.% Hf alloy. The
distributions of Al3+ and Hf4+ ions in the films indicate their similar migration rates,
which correlates with the similarity of the energies of Al3+-O2- and Hf4+-O2- bonds.
For an alloy containing ~95 at.% Hf, the film was largely nanocrystalline, with athin layer of amorphous oxide, of non-uniform thickness, at the film surface. The
formation ratios for the films on the alloys changed approximately in proportion to
the hafnium content of the films between the values for anodic alumina and anodic
hafnia, ~1.2 and 1.8 nm V-1 respectively.

123

ABSTRACTS of PUBLICATIONSCRGHUEnhanced Proton Conductivity of Amorphous Silicate Nanofilms
Y. Aoki, H. Habazaki, T Kunitake
ECS Transactions, 16, 407-412 (2009)
AlxSi1-xOn films exhibit a drastic change of proton conductivity acrossthe film by reducing its thickness to less than 100 nm. The temperature- andhumidity-dependence of conductivity of the sub-100 nm films is quite different
from those of the thicker films. Furthermore, in the former thickness range, thevalue of conductivity markedly increases with reducing the film thickness, and its
thickness dependence follows a power law with a fixed index of -2.1. Thissize-scaling effect can be explained by the percolation conductivity model that theprobability for percolating of the conductive moiety in AlxSi1-xOn films increases
with decreasing the thickness.

124

ABSTRACTS of PUBLICATIONSCRGHUSize-Scaling of Proton Conductivity in Amorphous Aluminosilicate
Acid Thin Films
Y. Aoki, H. Habazaki and T. Kunitake
Journal of the American Chemical Society, 131, 14399-14406 (2009)
Amorphous aluminosilicate nanofilms, a-Al0.1Si0.9Ox, exhibit uniquesize-enhancement of the proton conductivity along the thickness direction becauseof the presence of the zeolite-like, acid site network with the mesoscopically sized
dimension inside glass matrix. The dense films with the thickness of 22-1400 nm
were uniformly formed over the electrode substrate in nanometer thickness
precision by multiple spin-coating with a mixed precursor Sol. XANES
measurements indicated that the basic framework of a-Al0.1Si0.9Ox films was
similar to the zeolitic one, consisting of the corner-linkage of SiO4 and AlO4
tetrahedral units. These films revealed the complex temperature- andhumidity-dependency of proton conductivity by the existence of two kinds ofprotonic carriers: Bronsted acidic protons and Lewis acidic protons. The Bronsted
acidic protons could be persistent in amorphous films at around 500°C, as checkedby thermal desorption spectroscopy, so that the film exhibited thehumidity-independent proton conductivity at temperatures above 300°C.
Furthermore, the conductivity across the film increased in a power low by
reduction of the film thickness of to less than 120 nm. The observed scaling index
was 2.2 in agreement with the value of the theoretical index (2.3) of cluster size
scaling in a three-dimensional percolation system. This conduction behavior is
explicable by finite size-scaling of the highly conductive pathway based on theinterconnected Bronsted acid centers in the range of a few tens to hundreds ofnanometers.

125

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CRGHUOxide Scale Formed on Al-Mg Alloys in H2O-Containing
Atmosphere
T. Kurosaki, A. Yamauchi, K. Kurokawa
Applied Plasma Science, 17, 73-77 (2009)
Two kinds of Al-Mg alloys are oxidized in dry and wet conditions at 773 K
for 6hr. The oxidized specimens were observed and analyzed by TEM, SEM, EDS
and AES to investigate the effect of Mg content and water vapor on the structuresof scales formed on Al-Mg alloys by oxidation. At the all specimens, a thin oxide
layer was formed after oxidation. Despite of low Mg content, the surface oxide
layer composed of MgO and a sub-scale of Al2O3 or MgAl2O4 is also formed. The
range of scale thickness was 5 – 50 nm. The thickness of oxide layer increased
with Mg content. In addition, existence of water vapor also led to increase in thescale thickness. (Japanese)126

ABSTRACTS of PUBLICATIONSCRGHUThe Influence of Cr Addition on the High Temperature Corrosionof CoNiCrAlY Alloys
T. Sudiro, T. Sano, A. Yamauchi, S. Taniguchi, A. Kobayashi, K. Kurokawa
Advances in Applied Plasma Science, 7, 295-298 (2009)
CoNiCrAlY alloys with 0, 10, 20, and 30 mass% Cr were preparedusing a spark plasma sintering (SPS) technique. In order to clarify the influence of
Cr addition on the resistance against high temperature corrosion of CoNiCrAlY
alloys, the corrosion tests were carried out in Na2SO4 + 25mass% NaCl fused salt
at the elevated temperature of 923 K, 1073 K, and 1273 K for up to 100 hr.
Corrosion products in gas phase are mainly Cr2O3 in high Cr-CoNiCrAlY at 923 K
and Al2O3 in high Cr-CoNiCrAlY at 1073 K and 1273 K. Cr addition led todegradation of the high temperature corrosion resistance of CoNiCrAlY at 923 K
and at 1273 K. However, at 1073 K, Cr addition has a better corrosion resistance.

127

ABSTRACTS of PUBLICATIONSCRGHUReaction Behavior of Commercial Steels in Molten Lead-free
Solders
A. Yamauchi, A. Irisawa, S. Kawakubo, K. Kurokawa, J. Tanaka
15th Symposium on “Microjoining and Assembly Technology in Electronics”, 15,399-402 (2009)
The purpose of present study is to investigate the reaction behavior of various
commercial Fe-based alloys in molten lead-free solders. In low carbon steel andpure iron, these reaction behaviors are almost same. The change of thickness of
IMC layer that formed between solder and substrate obeys parabolic rate law. On
the other hands, the reaction behaviors of stainless steels are different. In SUS430,
the reaction area with solder is uniform, and then the interface between IMC andsubstrate is smooth. In SUS304 and SUS316, local corrosion occurs. The
morphology of interface between IMC and substrate shows kinds of pitting
corrosion. In addition, SUS316 has a good corrosion resistance in the molten
lead-free solder. The corrosion resistance for the molten lead-free solder depends
on the maintenance of sound scale formed on substrate. (Japanese)128

ABSTRACTS of PUBLICATIONSCRGHUFormation of Microstructures of Sn-based Alloys at MinuteStress Loading
H. Takagi, A. Yamauchi, A. Irisawa, S. Kawakubo, K. Kurokawa, J. Tanaka
15th Symposium on “Microjoining and Assembly Technology in Electronics”, 15,77-82 (2009)
The formation of sub-grain structures inside grains of β-Sn on Sn-based
alloys under stress loading has been reported. In this paper, we investigateddifferences of sub-grain size depended on additional elements for Sn-based alloys.
As a result, it was found that sub-grains of Al or Bi added specimens are very finecompared to that of pure Sn. However, the effect of Al addition dissolved on Cu
contained alloys. (Japanese)129

ABSTRACTS of PUBLICATIONSCRGHUCorrosion Behavior of Fe-based Alloys with Additional Elements
in Molten Lead-free Solders
T. Kawamoto，A. Yamauchi，S. Kawakubo，A. Irisawa，K. Kurokawa, J. Tanaka
19th Symposium of Micro Electronics, 19, 73-76 (2009)
The purpose of this study is to investigate the effects of additional elementson the corrosion behavior of Fe-based alloys and low carbon steel in the molten
lead-free solders. It is clear that the addition of chromium and titanium to the low
carbon steel improves the thickness of consumed substrate. On the other hand, theaddition of molybdenum for the improvement of thickness of consumed substrate
was not found. Moreover, the reaction layers that were formed on Fe-based alloys
were consisted of iron and tin intermetallic compounds (FeSn2). (Japanese)

130

ABSTRACTS of PUBLICATIONS

CRGHUEffect of Composition on Microstructure of Sn-Ag Solders
S. Kirai, A. Yamauchi, A. Irisawa, S. Kawakubo, K. Kurokawa, J. Tanaka
19th Symposium of Micro Electronics, 19, 77-80 (2009)
The effect of the composition and the cooling rate on the microstructure of
Sn-Ag and Sn-Ag-Cu solders has not been well investigated in detail. The purposeof this study is to investigate the effect of composition and the cooling rate on the
microstructures of the Sn-Ag and Sn-Ag-Cu solders. From the observation of
microstructures showed that the secondary phase that consisting of Sn and Ag3Sn
precipitated in Sn-Ag-Cu solders and their growth was observed. This coarsening
Ag3Sn affects the mechanical property of the solder. Thus, the microstructure
becomes complicated due to the change of the phase ratio. (Japanese)131

ABSTRACTS of PUBLICATIONSCRGHUBiointeractive and Bioreactive Nature of Nanomaterials
Fumio WATARI
Nano Biomedicine, 1, 2-8 (2009)
Biological reactions of nano/micro materials are discussed.
Nanomaterials are biointeractive in the sense that their size and existencethemselves possess the nature to induce the bioreaction to cells and tissue. They
are also bioreactive, since they induce the intrinsic functions of biologicalorganism in a generalized sense of both merit (bioactive) and demerit (toxic) for
human beings. The bilateral nature of the potentiality for both high functional
performance (nanotechnology) and unintentionally occurring biohazard(nanotoxicology) is the essential properties of nano/ micro materials.

132

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CRGHUAnalysis of Wear Debris Generated from
the Metal-on-metal Hip Joint
M.Uo, F.Watari, K.Asakura, N.Katayama, S.Onodera, H.Tohyama,
K.Hamada, S.Ohnuki
Nano Biomedicine, 1, 133-136 (2009)
The elemental concentration, shape and chemical state of debris
contained in the articular capsules of metal-on-metal hip joints were examined. Co
derived from Co-Cr alloy was detected with high concentration. By TEM
observation, some larger debris in several hundred nanometers and a lot of smaller
debris smaller than several ten nanometers were observed. The debris could beobserved in the severe metallosis region. Most of Co contained in the articular
capsules could be estimated as the metallic state by fluorescence XAFS analysis,
which provides high sensitivity for chemical state analysis. Therefore, themetallosis of the articular capsule could be assumed as mainly caused by themetallic debris.

133

ABSTRACTS of PUBLICATIONSCRGHUCapture of Bacteria by Flexible Carbon Nanotubes
T.Akasaka, F.Watari
Acta Biomaterialia, 5, 607-612 (2009)
Capture of bacteria with flexible carbon nanotubes (CNTs) was done invitro. Bundles of single-walled carbon nanotubes (SWCNTs) or multi-walledcarbon nanotubes (MWCNTs) was mixed with Streptococcus mutans. Precipitation
assays and colonyforming unit formation assays showed free S. mutans in thesolution was significantly decreased by the addition of the CNTs. Observation of
the precipitate by scanning electron microscopy showed bacterial adhesion to
CNTs. It has been shown that CNTs of different diameters have significantly
different effects on the precipitation efficiency, and the manners in which theycapture the cells are different. We found that MWCNTs (diameter ofapproximately 30 nm) had the highest precipitation efficiency, which was
attributable to both their adequate dispersibility and aggregation activity. Fromobservations by scanning electron microscopy, bundles of SWCNTs and thin
MWCNTs (diameter of approximately 30 nm), which were moderately flexible,
were easily wound around the curved surface of S. mutans. Bare CNTs having
high adhesive ability could be useful as biomaterials, e.g., as tools for theelimination of oral pathogens at the nano-level.

134

ABSTRACTS of PUBLICATIONS

CRGHUAdhesion of Human Osteoblast-like Cells (Saos-2)
to Carbon Nanotube Sheets
T.Akasaka, A.Yokoyama, M.Matsuoka, T.Hashimoto, S.Abe, M.Uo and F.Watari
Bio-Medical Materials and Engineering, 19, 147-153 (2009)
Carbon nanotubes (CNTs) exhibit excellent cell proliferation properties,
which can serve as a scaffold for cell culturing. However, there are only a few
reports on adhesion of osteoblast-like cells to a CNT sheet. In this study, weinvestigated adhesion of osteoblast-like cells to single-walled carbon nanotube(SWNT) and multi-walled carbon nanotube (MWNT) sheets and compared theseadhesions with that on a cell culture polystyrene dish by using a cell adhesion test
and a scanning electron microscope. The MWNT sheets exhibited faster adhesionof cells at an initial stage than SWNT sheets and cell culture polystyrene dish. The
number of attached cells on theMWNT sheets seemed to be greater than on SWNT
sheets and cell culture polystyrene. Moreover, the MWNT sheets exhibited both
high speed and good capacity for cell adhesion. However, the surface of the
MWNT sheets was such that it facilitated cell adherence but hindered the
spreading of the attached cells. Interestingly, cell adhesion to CNT sheets was
significantly influenced by pre-coating with serum. These results indicate that
CNT sheets would play an important role in adsorption of serum proteins, which
would consequently facilitate cell adhesion, and that the MWNT sheets have ahigh cell adhesiveness.

135

ABSTRACTS of PUBLICATIONS

CRGHUModification of the Dentin Surface
by using Carbon Nanotubes
T.Akasaka, K.Nakata, M.Uo, F.Watari
Bio-Medical Materials and Engineering, 19, 179-185 (2009)
Recent studies have shown that carbon nanotubes (CNTs) can be used as
biomedical materials because of their unique properties. CNTs effect nucleation ofhydroxyapatite, because of which considerable interest has been generated
regarding the use of CNTs in dentistry. However, there are only a few reports on
the use of CNTs as dental materials. In this study, we investigated the changes
induced in the surfaces of tooth slices by the application of a coating of CNTs byobserving CNTcoated tooth slices both macroscopically as well as under ascanning electron microscope. Further, we investigated the effect of CNT coatingon the tensile bond strength of dentin adhesives. CNTs adhered easily to the tooth
surfaces when tooth slices were suspended in a CNT-dispersed solution.
Interestingly, it was observed that CNTs selectively adhered to the surfaces ofdentin and cementum, possibly by adhering to their exposed collagen fibers. In
addition, the CNT coating did not affect the tensile bond strength of dentin
adhesives. These results indicate that coating of the teeth with CNTs can be apossible application of CNTs as dental materials.

136

ABSTRACTS of PUBLICATIONS

CRGHUTime-dependence and Visualization of TiO2 and Pt Particle
Biodistribution in Mice
S.Abe, C.Koyama, M.Uo, T.Akasaka, Y.Kuboki, F.Watari
J. Nanoscience Nanotechnology, 9, 4988-4991, (2009)
Micro- and nano-sized materials have received much attention regarding their bioc
ompatibility and toxicity. To understand the influence of such materials on animals, it
is very important to determine their internal distribution behavior. In this study, thebiodistributions of Pt and TiO2 micro- and nano-sized particles in mice were estimate
d and visualized by X-ray scanning analytical microscopy and inductively coupled pla
sma-atomic emission spectroscopy. We also determined the effect of particle size, diff
erence between metal and oxide, and time dependence for the distributions, because t
he biodistribution depends upon both the chemical character of materials and the sizeof particles. The results of the present study indicated that the difference in chemical
character had a greater effect than did particle size. We predict that X-ray scanning
analytical microscopy will be a useful method for studying biodistribution of micro- a
nd nano-sized particles, because this method requires no labeling or treatment of the target particles.

137

ABSTRACTS of PUBLICATIONSCRGHUInternal Distribution of Several Inorganic Microparticles in Mice
S.Abe, C.Koyama, T. Akasaka, M.Uo, Y.Kuboki, and F.Watari
Key Engineering Materials, 396-398, 539-542 (2009)
We observed the internal diffusion behavior of inorganic micro/nano particles throughoral administration. By oral exposure, the fed particles were absorbed through the digestivesystem then reached some organs after internal diffusion in the body. For example, TiO2
particles fed to mice were detected in the lung, liver, and spleen after 10 days of feeding.
Whereas, the absorption efficiency was extremely low compared with intravenous injection.
In a comparison of the simple amount of administration, oral exposure required 102 times ormore amount by intravenous injection for detection by an X-ray scanning analytical
microscope. During dental treatment, micro/nano particles from tooth or dental materials
would generate in the oral cavity, and some of the particles had a possibility to be
swallowed, absorbed through the digestive system, and then diffuse into the body. However,
our results suggest that biocompatible microparticles that are naturally taken orally affectanimals only rarely because of the low absorption efficiency.

138

ABSTRACTS of PUBLICATIONSCRGHUA DFT and MD Study on the Interaction of Carbon
Nano-materials with Metal Ions
S.Abe, F.Watari, T.Takada, H.Tachikawa
Molecular Crystals and Liquid Crystals, 505, 289-296 (2009)
The interaction of manganese (II) ion (Mn2+) with graphene surfaces have been investigated by means of density functional theory (DFT). Also, the molecular dynamics (MD) calculations using molecular mechanics-2 (MM2) potential functions have bee
n applied to the diffusion dynamics of Mn2+ on the graphene surface. Two graphenesheets (n= 19 and 52, where n means numbers of rings in each carbon cluster) wereconsidered as models of graphene surface in the present study. The B3LYP/LANL2
MB calculations showed that the Mn2+ ion is located in the ranges 2.28-2.46 Å fromthe graphene surface. Also, classical MD calculation was applied to diffusion process
es of the Mn2+ on the graphene surface (n= 52). The classical MD calculations show
ed that the Mn2+ ion diffuses from bulk to edge region at 300-600 K and is trappedin the edge region. The nature of the interaction between the Mn2+ ion and the grap
hene sheet was discussed on the basis of theoretical results.

139

ABSTRACTS of PUBLICATIONSCRGHUControlled Calcification using Polyanionic Macromolecules withan Active Reaction Center Analogue of Carbonic Anhydrase
S.Abe, T.Ishida, E.Yamatoya, D.Hayashi, T.Akasaka, M.Uo,
F.Watari, T. Takada
Nano Biomedicine, 1, 51-58 (2009)
Biomimetic macromolecules containing carboxyl and imidazole groups were synthe
sized. The complex of a zinc ion, a water molecule, and three imidazoles in a polym
er is expected to act as an active center analogue of carbonic anhydrase, a hydration
enzyme. The obtained polymer complex was applied to calcium carbonate formation.
In this study, we investigated the role of both functional groups on the calcification r
eaction. The presence of a carboxyl group drastically enhanced the biomineralization,
because it recognized and condensed the calcium ion at the first step of the calcificati
on reaction. The obtained zinc-imidazole complex selectively induced the formation ofvaterite, which is well-known to be a thermodynamically metastable polymorph of calcium carbonate. Interestingly, the results suggest that the active center analogue (zinc-imidazole complex) also stimulates introduction of the HCO3 ion to the calcium ion
recognition site.

140

ABSTRACTS of PUBLICATIONSCRGHUObservation of Biodistribution of Indium-Tin Oxide
Nanoparticles in Mice
S.Abe, T.Yonezawa, T.Akasaka, M.Uo, F.Uchida, F.Watari
Nano Biomedicine, 1, 70-74 (2009)
We have observed biodistribution of tin-doped indium oxide nanoparticles with the sizeof ca. 10 nm. After the particles administered into mice through the tail vein, the organs were
excited at several post-injection time then the specimens were subjected with X-ray scanning
analytical microscope. The obtained fluorescent X-ray images of indium element clearly
indicated that the injected nanoparticles reached and condensed temporally in the lung, liver,and spleen (especially, lung). The distributions among the organs were changed by the
post-injection time. The amount of nanoparticles in organs rapidly decreases within 4 weeks.

141

ABSTRACTS of PUBLICATIONSCRGHUBiodistribution Imaging of Magnetic Nanoparticles in Mice
Compared with X-ray Scanning Analytical Microscopy andMagnetic Resonance Imaging
S.Abe, I.Kida, M.Esaki, T.Akasaka, M.Uo, Y.Sato, B.Jeyadevan, Y.Kuboki,
M.Morita, K.Tohji, F.Watari
Bio-Medical Materials and Engineering, 19, 213-220 (2009)
Nano-sized particles have received much attention in view of their varied application ina wide range of fields. For example, magnetite (Fe3O4) nanoparticles have been investigatedfor various medical applications. In this study, we visualized the distribution of administeredmagnetic nanoparticles in mice using both X-ray scanning analytical microscopy (XSAM)
and magnetic resonance imaging (MRI). After administration, the nanoparticles were rapidly
dispersed via the blood circulation, and reached the liver, kidney and spleen. Using the
XSAM and MRI methods in a complementary fashion, the biodistribution of nano-sizedmagnetite particles was successfully visualized.

142

ABSTRACTS of PUBLICATIONS

CRGHU

In vivo Internal Diffusion of Several Inorganic Microparticles
Through an Oral Administration

S.Abe, C.Koyama, M.Esaki, T.Akasaka, M.Uo, Y.Kuboki, M.Morita, F.Watari
Bio-Medical Materials and Engineering, 19, 221-229 (2009)
We observed the internal diffusion behavior of inorganic micro/nanoparticles through oral administration. By oral exposure, the fed particles wereabsorbed through the digestive system then reached some organs after internal
diffusion in the body. For example, TiO2 particles fed to mice were detected in thelung, liver, and spleen after 10 days of feeding. Whereas, the absorption efficiency
was extremely low compared with intravenous injection. In a comparison of thesimple amount of administration, oral exposure required 102 times or more amountby intravenous injection for detection by an X-ray scanning analytical microscope.
During dental treatment, micro/nano particles from tooth or dental materials would
generate in the oral cavity, and some of the particles had a possibility to be
swallowed, absorbed through the digestive system, and then diffuse into the body.
However, our results suggest that biocompatible microparticles that are naturally
taken orally affect animals only rarely because of the low absorption efficiency.

143

ABSTRACTS of PUBLICATIONSCRGHUSynthesis and Characterization of a Water Aoluble
Multi-walled Carbon Nanotube and Its Biodistribution in Mice
S.Abe, D.Hayashi, T.Akasaka, M.Uo, Y.Kuboki, F.Watari, and T.Takada
Nano Biomedicine, 1, 143-150 (2009)
In this study, we have succeeded in synthesizing and characterizing awater-soluble multi-walled carbon nanotube. Nanotubes have been functionalized withmany hydrophilic carboxylic groups on the surface (3-10 wt%) by a poly-carboxylation
reaction and the obtained products show stable aqueous dispersion. To examine thenanotube’s preliminary biocompatibility, we injected the functionalized carbon nanotube
solution into mice through the tail vein. The time-profile of the subjects’ body weight had asimilar tendency to that of mise in a control group during 4-week post-injection
examination. The injected carbon nanotube derivatives were observed in specimens of thelung and liver using a transmission electron microscope. These results suggest that the
injected carbon nanotubes reach some organs through blood circulation after injection but
they did not cause serious acute toxicity in mice.

144

ABSTRACTS of PUBLICATIONSCRGHUDevelopment of a 3D Collagen Scaffold CoatedWith Multiwalled Carbon Nanotubes
E.Hirata, M.Uo, H.Takita, T.Akasaka, F.Watari, A.Yokoyama
Journal of Biomedical Materials Research Part B, 90B, 629–634 (2009)
Carbon nanotubes (CNTs) have attractive biochemical properties suchas strongcell adhesion and protein absorption, which are very useful for a cell
cultivation scaffold. Inthis study, we prepared a multiwalled carbon
nanotube-coated collagen sponge (MWCNTcoatedsponge) to improve the surface
properties of the collagen sponge, and its cell culturingproperties were examined.
The suface of the collagen sponge was homogeneously coated withMWCNTs bydispersion. MC3T3-E1 cells were cultured on and inside the
MWCNT-coatedsponge. The DNA content on the MWCNT-coated sponge after 1
week of culture was significantly higher than on an uncoated collagen sponge (p <0.05). There was no significantdifference between the estimated ALP activity
normalized by DNA quantity on the MWCNTcoatedsponge and that on theuncoated collagen sponge which is well known as one of the bestscaffolds for cell
cultivation. In addition, the MWCNT-coated surface shows strong celladhesion.
Therefore, the MWCNT-coated collagen sponge is expected to be a useful
3Dscaffold for cell cultivation.

145

ABSTRACTS of PUBLICATIONS

CRGHUImprovement in Cell Proliferation on Silicone Rubber by Carbon
Nanotube Coating
M. Matsuoka, T. Akasaka, T. Hashimoto, Y. Totsuka, F. Watari
Bio-Medical Materials and Engineering, 19, 155–162 (2009)
Silicone rubbers are widely used as tissue implants because of theirflexibility and chemical stability. However, they have limited cellular adhesivenessand may cause problems in the long term. In this study, a coating of carbon
nanotubes (CNTs) was applied to silicone rubber to improve its cellularadhesiveness. Scanning electron micrograph of this coating revealed that CNTs
had formed a densely packed meshwork; the Ra values and protein adsorption
capacity were enhanced. Although the contact angle did not change after coating, it
decreased after immersion into a culture medium. After cultivation for 6 d, while
Saos-2 cells were hardly observed on untreated silicone, the cells proliferated on
CNT-coated silicone. Thus, CNT coating might be a simple and effective solution
to problems associated with silicone implants.

146

ABSTRACTS of PUBLICATIONSCRGHUCulturing Osteoblast-like Cells on a Carbon Nanotube-coatedDish
M. Matsuoka, T. Akasaka, T. Hashimoto, Y. Totsuka, F. Watari
Nano Biomedicine, 1, 17-25 (2009)
The aim of this study was to investigate the influence of CNTs on cells
by culturing them in direct contact with CNTs. First, human osteoblast-like cells,
Saos-2 cells, were cultured on a CNT-coated culture dish and the cell morphology,
viability, adhesion, and alkaline phosphatase (ALP) activity of these cells werecompared to those cultured on a culture dish. Next, Saos-2 cells cultured on eachdish were subcultured onto culture dish, and the cell morphology and the ALP
activity were examined. The Saos-2 cells cultured on the CNTs showed a highviability that was similar to that of the cells on culture dish. Cell adhesion test
showed strong adhesiveness of the cells to multi-walled carbon nanotubes(MWCNTs) and morphological observation revealed many filopodia extending to
MWCNTs. After the subculture, this morphological change disappeared. These
results suggest that the Saos-2 cells a have high adhesiveness toward CNTs,
especially towards MWCNTs. Moreover, the morphological change in the cells
cultured on MWCNTs implies that CNTs did not induce denaturation of the cells.

147

ABSTRACTS of PUBLICATIONS

CRGHUEffect of Crosslinking Agent in Nanohydroxyapatite-collagen
Composite on Ectopic Bone Formation with BMP-2 Application
T.Tenkumo, T.Sugaya, M.Kawanami, M.Gelinsky, F.Watari
Nano Biomedicine, 1, 26-33 (2009)
Histological investigations of the nanohydroxyapatite-collagencomposite (nHAC) foil in tissue were carried out to evaluate its possible suitability
as a BMP-2 carrier for regeneration of periodontal tissue. The nanohydroxyapatite-collagen composite and its thin foil could be successfully fabricated with thecrosslinking agent of either 1-ethyl-3-(3-dimethylaminopropyl) carbodiimidehydrochloride (EDC) or ascorbic acid / copper chloride (AA/CC). They were
implanted into the subcutaneous tissue and tight muscle with and without BMP-2
for 1 and 2 weeks after surgery. nHAC was degraded and the inflammation in thesurrounding area was decreased with time. nHAC(AA/CC) was degraded earlier
and showed a better biocompatibility than nHAC(EDC). In the case of BMP-2
application, the different crosslinking agent showed an inverse effect. New boneformation was observed only in muscle for EDC and only in subcutaneous tissue
for AA/CC. The Present results suggested that the nHAC is suitable as the carrier
of BMP-2 with either the crosslinking agent of EDC or ascorbic acid / copper
chloride, and the suitable crosslinking agent should be selected depending ondesired conditions.

148

ABSTRACTS of PUBLICATIONSCRGHUIn Situ Observation of Dynamic Behavior of Liver Cells to Carbon
Nanotubes and Analysis of Cell Functions
S.Itoh, T.Taira, Y.Yawaka, F.Watari
Nano Biomedicine, 1, 95-108 (2009)
Carbon nanotubes (CNTs) are one of the most representative
nanomaterials that have newly appeared and drawn much attention for various
applications. To examine the effect of CNTs on biological organisms, the reaction
behavior of human hepatocytes, Hc cells, to CNTs was investigated in comparison
with phagocytes. After hepatocytes were incubated in the culture medium with theaddition of CNTs, CNTs were found in cytoplasms by OM (Optical Microscopy),
SEM (Scanning Electron Microscopy), TEM (Transmission Electron Microscopy).
In the successive observation using the time-lapse OM system, hepatocytes
showed the phagocytosis-like behavior to CNTs by changing their shapes andforming the long, straight pseudo-pods. The quantitative analysis showed that cell
activities to scavenge CNT debris were constant during the observation for morethan 22 hrs. Since these behaviors of hepatocytes apparently resemble those ofphagocytes, the cell functional analysis was done and compared by measuring theexpression of cytokines and superoxide dismutase (SOD) activity. When incubatedwith CNTs, THP-1 monocytes released TNF-α in a dose dependent manner to
CNT content, while the amount released from hepatocytes were very low and there
was almost no difference from control. These results indicate that hepatocytes havethe phagocytosis-like ability to uptake foreign objects. However, their mechanism
is completely different from that of phagocytotic cells in the point that they haveno functions to lead to inflammation through cytokine cascade as monocytes
exhibit. Throughout the study, hepatocytes could work without the acute toxicity
such as cell death by CNTs. In situ observation could image the dynamic behaviorof hepatocytes to perform the functions to treat the foreign objects. The results
confirm that liver is an important organ to deal with them under non-inflammatory
circumstances.

149

ABSTRACTS of PUBLICATIONS

CRGHUPhysical Properties of Aluminosilicate Nanotubes, Imogolite, as
Scaffold and Effect on Osteoblastic Mineralization
K.Ishikawa, T.Akasaka, Y.Nodasaka, N.Ushijima, M.Kaga, S.Abe, M.Uo,
Y.Yawaka, M.Suzuki, F.Watari
Nano Biomedicine, 1, 109-120 (2009)
Imogolite is a naturally occurring aluminosilicate clay mineral with ananotube structure of 2 nm in diameter and 60 nm-2 mm in length. In this study,
synthetic imogolite nanotubes were used to fabricate a scaffold for cell culture andthe properties of the resulting scaffold were compared with those of a conventional
culture dish and a carbon nanotube (CNT) scaffold. The surface characteristics of
the imogolite scaffold were drastically changed depending on the amount ofimogolite on the dish. With the increase of imogolite concentration, the surface
morphology of scaffolds changed from an island-like shape in random orientation
to a self-organized fiber texture aligned in the same direction, and finally fullcoverage in a random orientation with plural layers. Osteoblast-like cells (Saos-2)
cultured on imogolite showed a flat-form morphology developed in all directions
in contrast to a spindle-shaped morphology developed in one direction on cell
culture dishes (Cntl) and carbon nanotube scaffolds (CNT). The large growth ofthe cells proliferated on imogolite limited the smaller number of cells than the Cntl
and CNT. However, the amount of normalized protein per cell on imogolite
showed the value more than twice of that on Cntl. Imogolite contributed more to
the enlargement of cell volume than proliferation. The cells cultured on theimogolite scaffold become more strongly bound to the substrate and showed highosteoblas-tic mineralization than those cultured on Cntl and CNT. The results
indicate the good biocompatibility between cells and the imogolite scaffold, andsuggest that imogolite could be useful for various bioapplications, such as for the
fabrication of scaffolds for cell cultures, some useful proteins production (i.e.
antibody, enzyme) and surface modified implants.

150

ABSTRACTS of PUBLICATIONS

CRGHU

Surface Modification of Carbon Nanotubes with Calcifying
Solutions for Biomedical Applications
T.Koshikawa, Y.Kuboki, M.Uo, F.Watari
Nano Biomedicine, 1, 121-132 (2009)
In order to improve bio compatibility and biological function of carbon
nanotubes (CNTs), the surface of CNTs was modified by precipitating calcium
phosphate compounds in a calcifying solution. To accelerate calcification process
and efficacy of modification, a solution containing 6-times higher concentration of
calcium and phosphate ions than that of physiological body fluid was used (the6-times solution). Precipitation of calcium phosphate (Ca-P) upon CNTs wasinvestigated, concerning the incubation time, influence of concentration of CNTs,
elemental analyses of products and protein adsorption on the chromatographic
column. Time-dependent observation of the reaction products by SEM indicatesthat the moss-like precipitation of Ca-P at first, then the granular bodies appearedat the beginning of incubation. These moss-like bodies seemed to be replaced
gradually by granular bodies, and later, cotton fiber shaped structures appeared.
After 24 hr of incubation, the aggregation of spheroid bodies, composed ofhydroxyapatite and CNTs, became the dominant constitute of the products. Ca andP were detected by EDS even when there were no precipitations in SEM image,giving the evidence that the surface CNTs was slightly covered by calcium andphosphate compounds from very early stage. This was further strengthened by achromatographic result that the chromatography of slightly modified CNTs clearly
showed the greater affinity for an acidic protein (albumin) than the unmodified
CNT column. Combining with the evidence by EDS for Ca and P contents, thischromatographic result clearly indicates that the presence of calcium phosphates
on the surface of CNTs, even though the observation by SEM could not detect it.
The improvement of biocompatibility and the functionalization of CNTs could bedone using calcification solution and the possible applications were suggested forthe adsorption and release of various growth factors and medicines.

151

ABSTRACTS of PUBLICATIONS

CRGHUPreparation and Properties of Thermoplastic-resin-based
Nanocomposites for the Development of Esthetic Orthodontic
Wires
S.Yamagata, T.Akasaka, M.Uo, N.Ushijima, Y.Nodasaka, J.Iida, F.Watari
Nano Biomedicine, 1, 151-158 (2009)
Transparent PMMA/layered silicate nanocomposites were fabricated bya solution intercalation method. Montmorillonite (MMT), organically modified
with alkylammonium ions, was selected as the filler for reinforcement. Platelets oforganically modified MMT were well-dispersed macro-scopically in dissolved
PMMA. X-ray diffraction patterns showed that a peak regarded as a basal spacing
was shifted toward the lower 2θ values, indicating a diffusion of PMMA polymer
chains into interlayer regions of MMT. TEM micrographs revealed
well-intercalated and partially exfoli-ated structures of organically modified MMT.
Board-shaped specimens used for flexural tests were fabricated by compression
molding at 230°C. The specimens were transparent enough for their use as esthetic
orthodontic wires. The flexural modulus of the nanocomposites increased
marginally, relative to that of PMMA, with the increasing amount of clay.

152

ABSTRACTS of PUBLICATIONSCRGHUEarly-Stage Oxidation Behavior of Pt-Modified γ'-Ni3Al-BasedAlloys with and without Hf Addition
S. Hayashi, B. Gleeson
Oxidation of Metals, 71, 5-19, (2009)
The early-stage oxidation behavior in air of Pt-modified γ'-Ni3Al-based
alloys of composition (in at.%) Ni–22Al–30Pt with and without 0.5Hf wasinvestigated in terms of oxidation kinetics, scale evolution and Al2O3 phasetransformation. Oxidation exposures included heating to and short-term holds at
1150°C. Hafnium addition did not appear to affect microstructural evolution andgrowth rate of the oxide scales during heating to 1150°C; however, it was foundthat Hf delayed the metastable-to-α-Al2O3 phase transformation, thus allowing
continued fast growth of oxide scale. After the transient oxidation stage of up to
about 10 min (including heating time), Ni-rich metallic particles precipitated in thelower part of the metastable Al2O3 layer, due to a decrease in the oxygen potential
resulting from scale evolution. The present results indicated that the period ofoxide phase transformation was followed by the establishment of steady-stateoxidation kinetics. However, the steady-state kinetics were different for the twoalloy systems. Specifically, after complete phase transformation to α-Al2O3, rapid
growth of oxide grains occurred on the Hf-free alloy; whereas, the oxide grain size
remained small for the Hf-containing alloy. Such a difference of transformationand subsequent grain-growth behavior greatly affected oxide thickening kinetics.

153

ABSTRACTS of PUBLICATIONS

CRGHUCompositional Factors Affecting the Establishment andMaintenance of Al2O3 Scales on Ni-Al-Pt Systems
B. Gleeson, N. Mu, S. Hayashi
J. Mater., Sci., 44, 1704-1710, (2009)
The beneficial role played by platinum addition in promoting theformation of a protective Al2O3 scale on representative γ'-Ni3Al+γ-Ni coating
compositions during high-temperature oxidation is discussed. This beneficial effectcan be primarily ascribed to the fact that Pt is nonreactive, and its addition
decreases the chemical activity of aluminum in γ'. Related to the latter, Pt partitions
almost solely to the Ni sites in the ordered L12 crystal structure of γ', which has theeffect of amplifying the increase in the Al: Ni atom fraction on a given
crystallographic plane containing both Al and Ni. Such an effective Al enrichment
at the γ' surface kinetically favors the formation of Al2O3 relative to NiO. A further
contributing factor is that the Pt containing γ'-based alloys show subsurface Ptenrichment during the very early stages of oxidation. This enrichment reduces Ni
availability and can increase the Al supply to the evolving scale, thus kineticallyfavoring Al2O3 formation. This observed benefit of Pt addition promoting
exclusive Al2O3-scale growth is inferred to be a special form of the third-element
effect.

154

ABSTRACTS of PUBLICATIONSCRGHUThe Effect of S and Mn on the High-Temperature Oxidation and
Scale Spallation Behavior of Low-Carbon Steels
S. Hayashi, T. Sekimoto, K. Honda, T. Kinoshita, K. Tanaka, K. Ushioda,
T. Narita, S. Ukai
ISIJ International, 49, 1938-1944, (2009)
Early-stage oxidation behavior in air of low-carbon steels with andwithout S and Mn additions was investigated in terms of oxidation kinetics andscale spallation in a temperature range of 900 to 1150°C. S and Mn did not appear
to affect the growth rate of oxide scales within the given oxidation time, ~30 min,however it was found that S significantly enhanced oxide scale spallation. Scale
spallation occurred only on the S doped steels oxidized at temperatures more than
1000°C when the thickness of oxide scale exceeded about 120mm. This scale
spallation was confirmed to occur during cooling after the given oxidation time.
GD-OES analysis revealed that a significant amount of S enrichment occurred at
the oxide/steel interface, which was around 1 mass% on 100ppm S steel after 120sof oxidation at 1150°C. Such sulfur enrichment was speculated to be due toaccumulation of rejected S from surface recession during the high-temperatureoxidation. Observation of the steel surface after complete removal of the oxide
scale by quenching the steels into liquid nitrogen clearly indicates the formation of
eutectic Fe–FeS structure at scale/steel interface, resulting from a liquid phaseformation above 1000°C. Formation of sulfide, therefore a liquid phase at higher
temperature, greatly affected oxide scale spallation.

155

ABSTRACTS of PUBLICATIONSCRGHUHigh-Temperature Strength Characterization ofAdvanced 9Cr-ODS Ferritic Steels
S. Ukai, S. Ohtsuka, T. Kaito, H. Sakasegawa, N. Chikata, S. Hayashi
Materials Science and Engineering A, 510–511, 115–120 (2009)
Oxide dispersion strengthened (ODS) ferritic steels, which are the mostpromising candidate materials for advanced fast reactor fuel elements, have
exceptional creep strength at 973K. The superior creep property of 9Cr-ODS
ferritic steels is ascribed to the formation of a nonequilibrium phase, designated as
the residual ferrite. The yield strength of the residual ferrite itself has been
determined to be as high as 1360 MPa at roomtemperature fromnanoindentation
measurements. The creep strength is also enhanced by minimizing the number ofpacket boundaries induced by the martensitic phase transformation. The creep
strain occurs at a lower stress than that necessary for the deformation of theintragrain regions, which are strengthened by an interaction between nanosize
oxide particles and dislocations; this occurs by sliding at weaker regions such as at
the grain boundaries and packet boundaries. It is found that 9Cr-ODS ferritic steels
behave as fiber composite materials comprising the harder residual ferrite and thesofter tempered martensite.

156

ABSTRACTS of PUBLICATIONSCRGHU

Y2O3 Evolution and Dispersion Refinement in Co-Base ODS
AlloysL. Zhang, S. Ukai, T. Hoshino, S. Hayashi, X. Qu
Acta Materialia, 57, 3671–3682 (2009)
Co-base ODS alloys are potential materials for high-temperatureapplications. The evolution of Y2O3 during mechanical alloying (MA) andsubsequent annealing were studied with the main focus on the refinement ofparticle size by the addition of minor alloying elements. The results reveal that the
MA powder is characterized by ultrafine grains and high dislocation density,
which facilitate the decomposition of Y2O3. The decomposed Y2O3 thermally
precipitates at about 690°C. Ti, Zr and Ca cause the coarsening of oxide, while Hf
refines the oxide particle size and improves the homogeneity. The optimum Hfcontent is 1.2 wt.% and the resulting particle size is reduced to 9.6 nm with theprecipitation of partially coherent Y2Hf2O7 oxides. Higher Al content tends toresult in the formation of Al2O3 and Y3Al5O12 oxides, which are of larger size. The
threshold stress is predicted to be enhanced by the reduction of inter-particle
spacing. The refinement effect is also verified by hardness measurements.

157

ABSTRACTS of PUBLICATIONSCRGHUFormation of Ultrafine Grains in 9Cr-ODS Ferritic SteelN. Chikata, S. Hayashi, S. Ukai, S.Ohnuki, S. Ohtsuka and T. Kaito
Heat Treatment and Surface Engineering, 49, 557-560 (2009)
The high-temperature strength of 9Cr-ODS ferritic steel (Fe-9Cr-0.13C-2W-0.2Ti-0.35Y2O3) is owing to the unique structure, residual α-ferrite. In thisstudy, the strength and strength mechanism of the residual α-ferrite areinvestigated by using nanoindentation technique and transmission electron
microscope (TEM). Nano-hardness of the martensite reduces with increasing
tempering, whilst the residual α-ferrite maintains higher level of nano-hardness.
TEM observation confirmed that the residual α-ferrite contains ultrafine grains.
From the selected area diffraction (SAD) study with TEM, the residual ferrite
comprises ultrafine grains of 500 nm in size. It is concluded that highnano-hardness and high yield stress in the residual α-ferrite are attributed to thegrain refinement strengthening by the ultrafine grains.

158

ABSTRACTS of PUBLICATIONS

CRGHUDissociation-Precipitation Behavior of Oxide Particles
in Ni nano-Crystals
T. Hoshino, S. Ukai, S. Hayashi
Heat Treatment and Surface Engineering, 49, 643-646 (2009)
The Ni-10 mass% Y2O3 powders were mechanically alloyed for max
100 h by using planetary type of ball-mill. Subsequent heat treatment was
conducted at temperature ranging 373 K-1673 K. XRD and hardness measurement
were performed in as-MA and heat treated powders. Some of MA powders were
hot-pressed at 1473K and 10 kN for 3h, and TEM analysis was performed using
their thin foil specimens prepared by electrolytic polishing. In this test, the grain
size of Ni matrix is extremely reduced to 50 nm in nano-size, and Y2O3 particles
are concomitantly dissociated during initial stage of mechanical alloying of 3-10 h.
The subsequent heat treatment at temperature beyond 873 K induces
re-precipitation of Y2O3 oxide particles. The nanocrystalline structure of
Ni-10Y2O3 was maintained until coarsening of oxide particles that leads todecrease of pinning force for recrystallization over temperature of 1573 K

159

ABSTRACTS of PUBLICATIONSCRGHUFuel Pin Irradiation Test at up to 5 at% Burnup in BOR-60 for
Oxide-Dispersion-Strengthened Ferritic Steel Claddings
T. Kaito, S. Ukai, A. V. Povstyanko, V. N. Efimov
J.Nucl. Scie and Technol., 46, 529-533 (2009)
The fuel pin irradiation test of the ODS claddings, which weredeveloped as promising materials for higher burnup fuels, was carried out at highcladding temperatures of 700 and 650°C. in BOR-60. Vibro-packed MOX fuelswith low O/M ratio were used. The integrity of the ODS cladding fuel pins wasmaintained up to the burnup of 5.1 at.% and the neutron dose of 21 dpa, and the
FCCI of the ODS claddings was very small. These results suggest that the ODS
claddings and low O/M ratio fuels are the most appropriate fuel pin systems forhigh-burnup fuel. The irradiation of ODS cladding fuel pins continues in BOR-60
to a burnup of 15 at.%, and postirradiation data will be acquired.

160

ABSTRACTS of PUBLICATIONS

CRGHU

In-pile Creep Rupture Properties of ODS Ferritic Steel Claddings
T. Kaito, S. Ohtsuka, M. Inoue, T. Asayama, T. Uwaba, S. Mizuta, S. Ukai, T.
Furukawa, C. Ito, E. Kagota, R. Kitamura, T. Aoyama, T. Inoue
J. Nucl. Mater., 386-388, 294-298 (2009)
In order to examine irradiation effect on creep rupture strength of Oxide
Dispersion Strengthened (ODS) steel claddings, the in-pile creep rupture test was
conducted using Material Testing Rig with Temperature Control (MARICO)-2 inthe experimental fast reactor JOYO. Fourteen creep rupture events weresuccessfully detected by the temperature change in each capsule and the
gamma-ray spectrometry of the cover gas. Time to creep ruptures of six ODS steel
specimens were identified by means of Laser Resonance Ionization Mass
Spectrometry (RIMS), and no irradiation effect on creep rupture strength was
confirmed within the irradiation condition in the MARICO-2 test.

161

ABSTRACTS of PUBLICATIONS

CRGHUEffects of Aluminum on High-Temperature Strength of 9Cr‐ODS
SteelS. Ohtsuka, T. Kaito, M. Inoue, T. Asayama, S.W. Kim, S. Ukai 1, T. Narita,
H. Sakasegawa
J. Nucl. Mater., 386-388, 479-482 (2009)This paper discusses the effects of small amount of Al contamination(<0.1 wt%) on high-temperature strength and microstructure of the 9Cr–ODS steel.
Increasing Al concentration degraded the ultimate tensile strength as well as the
0.2% proof stress at 973 K and 1073 K accompanied by decreasing fraction of theelongated grain, i.e., residual-a ferrite acting as reinforcement phase. The decreaseof residual-a ferrite proportion provided by increasing Al is contrary to generalbehavior of conventional steels. Computer simulation on ferrite to austenite phasetransformation suggested that the fine oxide dispersion in the elongated ferrite
could be attributable to the preferential partitioning of Ti and W in ferrite than inaustenite at hot-extrusion process.

162

ABSTRACTS of PUBLICATIONSCRGHUAdvanced Structural Materials and Cladding
T. Allen, H. Burlet, R. K. Nanstad, M. Samaras and S. Ukai
Materials Research Society, Bulletin, 8, 20-27 (2009)
Advanced nuclear energy systems, both fission- and fusion-based, aim
to operate at higher temperatures and greater radiation exposure levels thanexperienced in current light water reactors. Additionally, they are envisioned tooperate in coolants such as helium and sodium that allow for higher operating
temperatures. Because of these unique environments, different requirements andchallenges are presented for both structural materials and fuel cladding. For coreand cladding applications in intermediate-temperature reactors (400–650°C), theprimary candidates are 9–12Cr ferritic–martensitic steels (where the numbers
represent the weight percentage of Cr in the material, i.e., 9–12 wt%) andadvanced austenitic steels, adapted to maximize hightemperature strength withoutcompromising lower temperature toughness. For very high temperature reactors(>650°C), strength and oxidation resistance are more critical. In such conditions,high-temperature metals as well as ceramics and ceramic composites are
candidates. For all advanced systems operating at high pressures, performance ofthe pressure boundary materials (i.e., those components responsible for containing
the high-pressure liquids or gases that cool the reactor) is critical to reactor safety.
For some reactors, pressure vessels are anticipated to be significantly larger andthicker than those used in light water reactors. The properties through the entire
thickness of these components, including the effects of radiation damage as afunction of damage rate, are important. For all of these advanced systems,
optimizing the microstructures of candidate materials will allow for improved
radiation and high-temperature performance in nuclear applications, and advanced
modeling tools provide a basis for developing optimized microstructures.

163

ABSTRACTS of PUBLICATIONSCRGHUSuper ODS Steels R&D for Fuel Cladding of Next Generation
Nuclear Systems 1) Introduction and alloy design
A. Kimura, R. Kasada, N. Iwata, H. Kishimoto, C.H. Zhang, J. Isselin, P. Dou, J.H.
Lee,N. Muthukumar, T. Okuda, M. Inoue, S. Ukai, S. Ohnuki, T. Fujisawa, F. Abe
Proc. of Int. Conf. on Advanced Power Plant, Paper 9220 (2009)
Cladding material development is essential for realization of highly
efficient high burn-up operation of next generation nuclear systems, where highperformance is required for the materials, that is, high strength at elevatedtemperature, high resistance to corrosion and high resistance to irradiation. Oxide
dispersion strengthening (ODS) ferritic steels are considered to be most adequate
for the cladding material because of their high strength at elevated temperature. In
this work, “Super ODS steel” that has better corrosion resistance than 9Cr-ODS
steel, has been developed for application to cladding of a variety of next generation
nuclear systems. In the following ten papers, the resent experimental results of“Super ODS steel” R&D, which indicate that many unexpected preferable features
were found in the mechanical properties of nano-sized oxide dispersion high-Cr
ODS ferritic steel. A series of paper begins with alloy design of “Super ODS
steel”. Corrosion issue requires Cr concentration more than 14wt.%, but aging
embrittlement issue requires less than 16wt.%. An addition of 4wt.%Al is effective
to improve corrosion resistance of 16wt.%Cr-ODS steel in SCW and LBE, while itis detrimental to high-temperature strength. Additions of 2wt.%W and 0.1wt.%Ti
are necessary to keep high strength at elevated temperatures. An addition of small
amount of Zr or Hf results in a significant increase in creep strength at 700 ºC in
Al added ODS steels. Tube manufacturing was successfully done for the superODS steel candidates. “Super ODS steel” is promising for the fuel cladding
material of next generation nuclear systems, and the R&D is now ready to proceed
to the next stage of empirical verification.

164

ABSTRACTS of PUBLICATIONSCRGHUSuper ODS Steels R&D for Fuel Cladding of Next Generation
Nuclear Systems 2) Effect of Minor Alloying Elements
S. Ohnuki, N. Hashimoto, S. Ukai, A. Kimura, M. Inoue, T. KaitoT. Fujisawa,
T. Okuda, F. Abe
Proc. of Int. Conf. on Advanced Power Plant, Paper 9306 (2009)
Oxide dispersion strengthened (ODS) ferritic steels are one of the candidate
materials for fuel cladding of next generation nuclear systems because of its strength athigh temperatures and good resistance to irradiations. Presently, the effects of alloying
elements, such as Cr and Al, on distribution of oxide particle have been investigated to
improve materials properties.
However, it has been the matter that mechanical properties
were affected seriously by coarsening of oxide particles by addition of Al. On the other
hand, it has been observed that the addition of IVa family elements leads to finer and more
uniform nano-sized oxide dispersion. The purpose of this study is to investigate the effect ofminor element addition on the size distribution of oxide particles by transmission electron
microscopy (TEM). The chemical compositions of the mechanical alloyed mixed powders
were Fe-16Cr-4Al-mY2O3-nZr or mHf. The mechanical alloying was carried out for 48
hours under Ar atmosphere, and then the mixed powder was annealed at 1150 C for 2 hours
in vacuum. The powders were Ni-plated and made into a plate specimen. TEM disks wereprepared from the plate after mechanically-polishing to 50µm thick and finallyelectro-polished for TEM observations. TEM observation was performed using a 200 kV
microscope. On all the observed specimens, oxide particles of ~ 50nm diameter wereobserved. It was found that the addition of IVa family elements effectively reduced the sizeof oxide particles. From the result of size and number density measurements, the optimum
composition was considered to be 0.35Y2O3-0.3Zr and 0.35Y2O3-0.6Hf in mass %. It isnotable that the oxide formation energy of Zr and Hf is lowest among the IVa elements
investigated in this work. The strong affinity may suppress the diffusion of the elements
during fabrication process, and then results in the formation of fine oxide particles in highdensity.

165

ABSTRACTS of PUBLICATIONSCRGHUSuper ODS Steels R&D for Fuel Cladding of Next Generation
Nuclear Systems 3) Development of high performance attrition
type ball mill
T. Okuda, M. Fujiwara, T. Nakai, K. Shibata, A. Kimura, M. Inoue, S. Ukai, S.
Ohnuki, T. Fujisawa, F. Abe
Proc. of Int. Conf. on Advanced Power Plant, Paper 9229 (2009)
The mechanical properties of the oxide dispersion strengthened (ODS)
ferritic steels at elevated temperatures depend on oxide particle sizes and theirinterspacing. The formation process of oxide particles is influenced by oxygen
content in pre-mixed metal powder or pre-alloyed metal power, where the oxygen
was mixed or contaminated during the mechanical alloying (MA) and thefollowing consolidation process. In the present study, a high-performance attritionball mill was designed and fabricated to make fine MA powder without oxygen
contamination from atmosphere. Furthermore, all the manufacturing processes ofscreening and filling the powder in a capsule for extrusion are performed in theinert gas atmosphere. The optimum excess oxygen contents of the candidate ODS
steels can be defined by utilizing these controlled equipments. The effects oftitanium, zirconium, hafnium, and oxygen addition on the formation of yttrium
based complex oxide particles were investigated for Fe-16Cr-4Al-2W-0.1Ti-0.35Y2O3 ODS ferritic steels with the excellent corrosion resistance.

166

ABSTRACTS of PUBLICATIONSCRGHUSuper ODS Steels R&D for Fuel Cladding of Next Generation
Nuclear Systems 5) Mechanical properties and microstructure
R. Kasada, S.G. Lee, J.H. Lee, T. Omura, C.H. Zhang, P. Dou, J. Isselin, A.
Kimura, M. Inoue, S. Ukai, S. Ohnuki, T. Fujisawa, T. Okuda, F. Abe
Proc. of Int. Conf. on Advanced Power Plant, Paper 9072 (2009)
Oxide dispersion strengthened (ODS) ferritic steels are promising material forthe next generation fission reactor fuel pin cladding. In the present study, the relationshipbetween mechanical properties, such as tensile strength, fracture toughness andductile-brittle transition behavior, and microstructure of the Al-added ODS ferritic steels
were investigated. The mechanism of improvement of creep strength by Zr or Hf addition is
also proposed on the basis of the result of TEM observation. The ODS ferritic steels used in
the present study were SOC-1 which is a reference material for the SUPER ODS R&D, andits variations with an addition of minor elements, such as Zr and Hf (SOC-14 and 16). The
chemical compositions of SOC-1 is Fe (bal.)-16.1Cr-3.4Al-0.09Ti-0.27Y2O3 in wt.%.
Pre-mixed powders of the compositions were mechanically-alloyed in high purity Ar gas
and canned in vacuum. Finally, hot-extrusion was carried out to be about 25 mm diameter at
1150 °C, followed by a heat treatment for 1 hour at 1150 °C. Tensile tests were carried out
at room temperature. Sub-sized 1.5 × 1.5 × 20.0 mm V-notch specimens were used for theCharpy impact tests. The crystallographic anisotropy was also investigated by Schulz’sreflection method using the Rigaku TTR-III X-ray diffractometer (XRD). Morphology ofthe nano-scale oxide particles in the ODS steels were also investigated by using fieldemission transmission electron microscopy (FE-TEM). As one of the results,
newly-developed Al-added ODS ferritic steels with Zr or Hf showed much better creep
strength than the ODS ferritic steels without Zr/Hf addition. This successful development
was achieved by microstructural modification of nano-oxide particles: The addition of Zr or
Hf resulted in the reduction and increases of the size and number density of the oxide
particles, respectively. Furthermore, the addition of Zr or Hf enhanced the formation ofgrain boundary precipitation of carbides and oxides in high density. Both effects play
important role in the improvement of the creep strength.

167

ABSTRACTS of PUBLICATIONSCRGHUSuper ODS Steels R&D for Fuel Cladding of Next Generation
Nuclear Systems 6) Corrosion Behavior in SCPW
J.H. Lee, A. Kimura, R. Kasada, N. Iwata, H. Kishimoto, C.H. Zhang, J. Isselin, P.
Dou, N. Muthukumar, T. Okuda, M. Inoue, S. Ukai, S. Ohnuki, T. Fujisawa,
F. AbeProc. of Int. Conf. on Advanced Power Plant, Paper 9223 (2009)
Generally, corrosion is a critical issue for cladding materials, especially, in severcorrosion environment like supercritical pressurized water (SCPW). It is also expected thatin reactor water chemistry can be influenced by energy particle irradiation. Therefore, it isessential to develop corrosion resistant cladding material for realization of highly efficienthigh burn-up operation of next generation nuclear systems. In this work, the effects of alloy
elements on the corrosion behavior in SCPW were investigated for a series of ODS steels todesign alloy compositions for corrosion resistant super ODS ferritic steels. Corrosion tests
were carried out for the ODS steels with different concentrations of Cr and Al in SCPW at
400, 500 and 600 ºC at 25MPa. The corrosion of the ODS steel was enhanced by thedecrease in the concentration of Cr and Al. In 19Cr-ODS steels, the addition of 4wt.%Al isnot effective to improve corrosion resistance, but it is very effective in 16Cr-ODS steels. It
was revealed by EPMA measurements that a very thin alumina film was formed on thespecimen surface of the Al added ODS steels, which suppressed the corrosion of Al added
ODS steels. The addition of Hf resulted in a significant increase in the corrosion rate.
However, the corrosion rate was increased a little by the addition of Zr. The corrosion rateof SUS430, which contained 16wt.%Cr, was much higher than 16Cr-ODS steel. Thissuggests that nano-sized oxide particles dispersion and very fine grains play important rolein suppression of the corrosion. A systematic study of the effect of grain size on corrosion
rate indicates that the corrosion rate decreases with decreasing grain size below 1 m, while
above it, the corrosion rate is not influenced by grain size. Furthermore, the nano-sizedoxide particles are also considered to cause the suppression of corrosion in comparison to
SUS430. Steady strain rate tests (SSRT) were carried out at 500 ºC for ODS steels. The
effects of strain rate on the stress-strain behavior was investigated for the ODS steels. No
effect was observed on the stress-strain behavior and fracture mode: in both the case ductile
fracture was observed with showing dimples on the fracture surface.

168

ABSTRACTS of PUBLICATIONSCRGHUSuper ODS Steels R&D for Fuel Cladding of Next Generation
Nuclear Systems 7) Corrosion Behavior and Mechanism in LBE
H. Sano1, T. Fujisawa1, A. Kimura, M. Inoue, S. Ukai, S. Ohnuki, T. Okuda,
F. AbeProc. of Int. Conf. on Advanced Power Plant, Paper 9308 (2009)
Corrosion of structural materials is one of the important problems whenlead-bismuth eutectics (LBE) is used as coolant material in next generation nuclear
systems. In this study, dissolution experiments of synthetic Fe-Cr-Al alloys anddeveloped super ODS steel candidates into LBE under several partial pressures ofoxygen were conducted. Dissolution behavior of major components in suchsteels into LBE was investigated. Interfacial behavior between LBE and steels
was also observed. In addition, partial potential diagrams of the Fe-Cr-Al-O
system at several conditions were established as basic data.
From the potential
diagrams, the partial pressure range of oxygen was estimated for the stable
protective oxide layer formation at the interface. At lower oxygen partialpressures than the pressure that is adequate for the formation of the stable oxide
layer, a rough oxide layer was formed at the interface in all samples, and the ally
elements dissolved into LBE through it. On the other hand, at the oxygen partialpressure to form stable oxide layer, a dense and very thin oxide layer was formed
especially on the higher aluminum content steel, preventing the alloy dissolution
into LBE. From the results, aluminum and chromium content in steel were very
important for preventing the corrosion by LBE.

169

ABSTRACTS of PUBLICATIONSCRGHUSuper ODS Steels R&D for Fuel Cladding of Next Generation
Nuclear Systems 9) Damage Structure Evolution underElectron-Irradiation
S. Ohnuki, N. Hashimoto, S. Ukai, A. Kimura, M. Inoue, T. Kaito, T. Fujisawa,
T. Okuda, F. Abe
Proc. of Int. Conf. on Advanced Power Plant, Paper 9307 (2009)
ODS ferritic steels are one of the candidate cladding materials of the advanced
fission reactors, because of their good mechanical properties and the irradiation resistance.
It is expected that the nano-scaled fine oxide particles are the key of the good performanceof the steels. However, no information is available for the effects of nano-scaled oxide
particles on the formation of irradiation damage structures. In this study, an in-situ TEM
observation of microstructure evolution was carried out to investigate the effects ofnano-scaled oxide particles on the formation of dislocation loops. The materials
compositions were 16Cr-0.35Y2O3 for standard, and the others were added with minor
elements of Ti, Zr and/or Hf. The elemental powders were mechanically alloyed,
hot-extruded, and followed by a heat-treatment at 1150 ºC. Electron-irradiation and in-situ
observations were performed at 500 ºC to 10 dpa by using high voltage electron microscopeof Hokkaido University, operated at 1250 kV. The irradiated area was 2 m in diameter andthe thickness was measured by the number of diffraction fringes. The characterization of theoxide particles was performed by SADP, high resolution image and FFT/IFFT methods. In
all of steels, black dots-like fine dislocation loops were formed during the irradiation, andthe evolution behavior depended on the type of additional elements but not sensitive to theheat-treatment conditions. Standard steel showed clear formation of the loops that grew to
90 nm at this condition. The steel without Al, the loop formation was not well progressed. Incase of the steels added with Zr or Hf, they showed an intensive suppression of the loop
growth, as we expected from the results of the model alloy experiment. The results indicatethat a large number of oxides enhanced the mutual recombination of the interstitials andvacancies, especially at the particles/matrix interfaces. The particles were identified ascomplex oxide of Y and added elements which have high affinity to oxygen. It was also
confirmed that all of the particles were not changed in the size during the irradiation,
indicating high irradiation-resistance at this condition.

170

ABSTRACTS of PUBLICATIONSCRGHUSuper ODS Steels R&D for Fuel Cladding of Next Generation
Nuclear Systems 10) Cladding Tube Manufacturing and Summary
S. Ukai, S. Ohnuki, S. Hayashi, T. Kaito, M. Inoue, A. Kimura, T. Fujisawa,
T. Okuda, F. Abe
Proc. of Int. Conf. on Advanced Power Plant, Paper 9232 (2009)
The high Cr oxide dispersion strengthened (ODS) ferritic steels with superior corrosion
resistance have been developing for the fuel elements of the next generation nuclear energy
system. In order to realize the prospective super ODS fuel element, cladding tube
manufacturing is a crucial technology. In this study, recrystallization behavior of the ODS
sheet specimens as well as practical tubes was investigated with repeating a set of coldrolling and heat treatment. Cold–rolling and recrystallization tests were performed using
sheets, which were cut from the extruded bar of the standard ODS steel. At 50 %reduction rate, Vickers hardness is around 350 Hv. Only some dislocation recovery occurs
after 1 hour heat treatment below 1100 ºC, while above this temperature recrystallization
being concomitant with hardness reduction to 250 Hv occurs. The cold rolled texture shows<110> axis parallel to the rolling direction and mainly {111} plane along the rolling section
with slightly inclining to {001}. This texture is drastically changed to recrystallized texture,
which is <100> axis parallel to rolling direction and {110} plane along the rolling section.
From the mother tubes in the dimension of 18 mm outer diameter and 3 mm thickness,
cladding tubes with 8.5 mm OD and 0.5 mm TH were manufactured by using pilger–mill.
The cold rolling was repeated four times with each reduction rate of 40–50 %, andintermediate heat treatment was performed. The intermediate heat treatment temperature
was shifted from 1100 ºC to 800 ºC after 1st , 2nd and 3rd cold–rolling. The final heat
treatment was successfully conducted at 1150 ºC for 1h to make perfectly recrystallized
structure. Through this test, it was demonstrated that super ODS steels have an adequate
capability for cladding manufacturing. The ODS steel, 16Cr-4Al-2W-0.1Ti added withsmall amount of Zr(Hf), is the prime candidate of “Super ODS steel” which has highstrength at elevated temperatures, high resistance to corrosion in SCPW and LBE, and highresistance to irradiation. Tube manufacturing was also successfully done for the Super ODS
steel. It is considered that Super ODS steels R&D is facing to the next stage of verification
experiment towards realization of fuel pins of next generation nuclear systems.

171

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CRGHU

In-situ TEM Observations of the Crystallization Process of
Solution-Prepared MoS2 Amorphous Particles
Akinori Hanzawa, Toshihiro Shimada, Tatsuya Hasegawa, Takahiro Sato, Takeo
Kamino and Tetsu Yonezawa
Journal of Nanoscience and Nanotechnology, 9, 6736-6740 (2009).

The crystallization of polymer-mixed amorphous molybdenum sulfide wasobserved in-situ by a TEM equipped with a heated specimen holder. High electron
beam irradiation induced the formation of a crystal structure with a lattice spacingof 0.62 nm, which corresponds to the layer spacing of MoS2. With a lower electrondose, a possible new crystal structure of molybdenum sulfide with several fringe
spacings was identified at room temperature. An ordered layered structure Of
MoS2 appeared after annealing at 600 °C. The completely different crystal phasefound here might be responsible for the high temperature required for theformation of the MoS2 layered structure.

172

ABSTRACTS of PUBLICATIONS

CRGHU

Sulfonate Group-modified FePtCu Nanoparticles as a Selective
Probe for LDI-MS Analysis of Oligopeptides from a Peptide
Mixture and Human Serum Proteins
Hideya Kawasaki, Akira Tarui, Takehiro Watanabe, Kazuyoshi Nozaki, Tetsu
Yonezawa, and Ryuichi Arakawa
Analytical and Bioanalytical Chemistry, 395, 1423-1431 (2009)
Bare FePtCu nanoparticles (NPs) are first prepared for laser
desorption/ionization mass spectroscopy (LDI-MS) analysis as affinity probes toselectively trap oppositely charged analytes from a sample solution. Our present
results demonstrate bare FePtCu NPs to be a potentially useful matrix forsurface-assisted laser desorption/ionization mass spectroscopy (SALDI-MS), forthe analysis of small proteins and peptides. The upper detectable mass range of
peptides was approximately 5 kDa, and the detection limit for peptides
approximately 5 fmol. Sulfonate group-modified FePtCu nanoparticles(FePtCu-SO3- NPs), with ionization being independent of the solution pH, caninteract with a positively charged analyte, and the analyte-bound NPs can beseparated from the reaction supernatant by centrifugation or an external magnetic
field. An oligopeptide, Gly-Gly-Tyr-Arg (GGYR) from an oligopeptide mixture
containing Asp-Asp-Asp-Asp (DDDD), Gly-Gly-Gly-Gly (GGGG) and GGYR,
was detected using SALDI-MS with FePtCu-SO3- NPs employing electrostaticinteraction. Furthermore, FePtCuSO3- NPs can detect lysozyme (Lyz) in humanserum through the electrostatic attraction between positively charged Lyz and
FePtCu-SO3(-) NPs at pH 8, while detection of negatively charged albumin inhuman serum is not possible.

173

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CRGHU

In-situ observation of silver nanoparticle ink at high temperature
Tetsu Yonezawa
Bio-Medical Materials and Engineering, 19, 29-34 (2009)
In-situ TEM (transmission electron microscopy) of silver nanoparticle ink athigh temperature was carried out. Into a carbon film tube coating the spiraltungsten filament which was attached to the TEM specimen holder, a silver
nanoparticle ink was injected. After evaporation, silver nanoparticles with anaggregated structure could be observed. The temperature of the tungsten wire canbe controlled by DC current supplied by dry batteries. Fusion of smaller
nanoparticles was observed at a higher temperature and some particles wereincorporated to larger particles. This technique can be generally used to consider
the sintering temperature of such metal nanoparticles.

174

ABSTRACTS of PUBLICATIONSCRGHUDetailed Investigation on the Possibility of Nanoparticles of
Various Metal Elements for Surface-Assisted Laser
Desorption/Ionization Mass Spectrometry
Tetsu Yonezawa, Hideya Kawasaki, Akira Tarui, Takehiro Watanabe, Ryuichi
Arakawa, Toshihiro Shimada, and Fumitaka Mafuné
Analytical Sciences, 25(3), 339-346 (2009). Selected as a Hot Article
In this paper, we describe systematic detailed considerations of the feasibilityof using various metal nanoparticles for organic-matrix-free surface-assisted laser
desorption/ionization mass spectrometry (SALDI-MS). In order to avoid theinfluence of organic molecules on the nanoparticles, stabilizer-free barenanoparticles of Ag, Au, Cu and Pt were prepared by laser ablation. Although all
metal nanoparticles absorbed N2 laser light (337 nm) energy, the performance ofdesorption/ionization of a representative peptide, angiotensin I, strongly depended
on the metal element. Citrate buffer was used as a proton source; it reduced theamount of alkali cation adducts present. Then, protonated molecules of analytes
predominated in the mass spectra when Au and Pt nanoparticles were used. Pt
nanoparticles showed the highest performance in SALDI-MS, owing to theirsmaller heat conductivity and higher melting temperature. The selective desorptionof a cationic surfactant with longer alkyl chains and a peptide with methionine wasalso observed.

175

ABSTRACTS of PUBLICATIONSCRGHUPlugging a Molecular Wire into Photosystem I: Reconstitution of
the Photoelectric Conversion System on a Gold Electrode
Nao Terasaki, Noritaka Yamamoto, Takashi Hiraga, Yoshinori Yamanoi, Tetsu
Yonezawa, Hiroshi Nishihara, Tsutomu Ohmori, Makoto Sakai, Masaaki Fujii,
Akihiko Tohri, Masako Iwai, Yasunori Inoue, Satoshi Yoneyama, Makoto
Minakata, Isao Enami
Angewante Chemie-International Edition, 48(9), 1585-1587 (2009)
Photoinduced electron transfer occurs from photoexcited P700 in
photosystem I (PSI) to a gold surface (see picture). A novel molecular connector
system is used, in which an artificial molecular wire, which is assembled on thegold surface, was plugged into PSI by reconstitution. Analysis of the photoelectrontransfer kinetics proved both the output of electrons from PSI and the effectivenessof the molecular wire.

176

ABSTRACTS of PUBLICATIONSCRGHUGold-Nanoparticle-Supported Silicon Plate with Polymer Micelles
for Surface-Assisted Laser Desorption/Ionization Mass
Spectrometry of Peptides
Akira Tarui, Hideya Kawasaki, Takuma Taiko, Takehiro Watanabe, Tetsu
Yonezawa, and Ryuichi Arakawa
Journal of Nanoscience and Nanotechnology, 9, 159-164 (2009).
We developed surface-assisted laser desorption/ionization mass spectrometry(SALDI-MS) using nanocomposite films of cationic diblock copolymer micelles[poly(styrene-b-N-methyl-4-vinyl pyridinium iodide)] and ammonium citrated Au
nanoparticles (AuNPs) on silicon. The nanocomposite film on silicon was suitablefor use as a material for matrix-free LDI-MS of peptides due to its low matrix
background from Au clusters and high ionization efficiency; this plate successfully
ionized angiotensin I, and also insulin in the proton adduct forms, in contrast tomethods using only AuNPs and those using nanocomposite films of cationicpolymer in conjunction with Au NPs. The high ionization efficiency is discussed
from the viewpoint of nanoparticle distribution controlled by polymers on the plate(aggregates vs. nonaggregates).

177

ABSTRACTS of PUBLICATIONSCRGHUBasic and Recent Topics of Metal Nanoparticles
Atsushi Hyono and Tetsu Yonezawa
Shikizai Kyokai Shi, 82, 468-474 (2009)This is a review article on basic and recent topics of metal nanoparticles(Japanese).

178

ABSTRACTS of PUBLICATIONSCRGHUPalladium nanoparticle seeded electroless metallization of
Al/Al2O3 surfaces
H. Jha, T. Kikuchi, M. Sakairi and H. Takahashi
Materials Letters, 63, 1451- 1454 (2009)

A simple method for the formation of palladium nanoparticles on
aluminum and aluminum oxide surface is demonstrated. In the present method, thepalladium nanoparticles obtained directly on the solid surface by immersing thespecimen in palladium(II)acetate solution followed by reduction to metallic
palladium by using sodium hypophosphite. In the investigation, as-received, boiled,electropolished and anodized aluminum was used as substrate. Additionally, themethod is combined with the electroless nickel plating, which facilitates two steps
metallization technique on the respective surfaces. In these cases, specimens werefirst immersed in palladium(II)acetate solution followed by immersion inelectroless nickel plating solution, where, palladium reduced on the specimen
surface providing catalytic site for the subsequent electroless nickel deposition.
Using the technique, about 6 to 8.5 µm thick Ni–P metallic layer was deposited on
the specimen surface.

179

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CRGHU

Growth of multioxide planar film with the nanoscale inner
structure via anodizing Al/Ta layers on Si
A. Mozalev, A.J. Smith, S. Borodin, A. Plihauka, A.W. Hassel, M. Sakairi, H.
Takahashi1,
Electrochimica Act, 54, 935-945 (2009)

An Al/Ta bilayer specimen prepared by a successive sputter-depositionof a 150-nm tantalum layer and a 180-nm aluminium layer onto a silicon wafer isanodically processed in a sequence of steps in oxalic acid electrolytes, at voltagesof up to 53 V, which generates a 260-nm alumina film with well-ordered
nanoporous structure. Further potentiodynamic reanodizing the specimen to 220 V
causes the simultaneous growth of a 65-nm tantalum oxide layer beneath thealumina film and an array of oxide ‘nanocolumns’ (50 mn wide, 80 nm apart,7 × 109 cm−2 population density) penetrating the alumina pores and reaching
precisely to the top of the alumina film. The complete filling of the alumina poresis assisted by the high Pilling–Bedworth ratio for Ta/Ta2O5 and a substantially
increased transport number for tantalum species (0.4), which is an average value ofall migrating tantalum ions with different oxidation states. The nanocolumns areshown to be composed of a unique, regular mixture of Ta2O5 (dominating amount),
suboxides TaO2 and TaOx (0.5 < x < 1), Al2O3, metallic Ta and Al aggregates,
tantalum diboride (TaB2) and oxidized boron from the electrolyte. The ionictransport processes determining the self-organized growth of these planar oxide
nanostructures are considered and described conceptually.

180

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CRGHU

Growth of porous type anodic oxide films at micro-areas on
aluminum exposed by laser irradiation
Tatsuya Kikuchia, Masatoshi Sakairia and Hideaki Takahashi
Electrochimica Acta, 54, 7018-7024 (2009)

Aluminum covered with pore-sealed anodic oxide films was irradiatedwith a pulsed Nd–YAG laser to remove the oxide film at micro-areas. The
specimen was re-anodized for long periods to examine the growth of porous
anodic oxide films at the area where substrate had been exposed by measuring
current variations and morphological changes in the oxide during the re-anodizing.
The chemical dissolution resistance of the pore-sealed anodic oxide films in an
oxalic acid solution was also examined by measuring time-variations in rest
potentials during immersion.
The resistance to chemical dissolution of the oxide film became higher
with increasing pore-sealing time and showed higher values at lower solution
temperatures. During potentiostatic re-anodizing at five 35-µm wide and 4-mm
long lines for 72 h after the film was removed the measured current was found toincrease linearly with time. Semicircular columnar-shaped porous type anodic
oxide was found to form during the re-anodizing at the laser-irradiated area, andwas found to grow radially, thus resulting in an increase in the diameter. After longre-anodizing, the central and top parts of the oxide protruded along thelongitudinal direction of the laser-irradiated area. The volume expansion during
re-anodizing resulted in the formation of cracks, parallel to the lines, in the oxide
film formed during the first anodizing.

181

ABSTRACTS of PUBLICATIONS

CRGHUEffect of Potential, Temperature, and Fluoride Ions on theRepassivation Kinetics of Titanium in Phosphate Buffered Saline
Solution with the Photon Rupture Method
M. Sakairi, H. Miyata, T. Kikuchi and H. Takahashi,
Laser chemistry, 2009, Article ID 436065, 8 pages, (2009)

The effect of the applied potentials, temperature, and F- ions on thelocalized repassivation kinetics of titanium was investigated by the photon rupture
method, PRM, and electrochemical techniques in phosphate buffered saline
solution. The log I vs. log t plots after laser beam irradiation showed a rapid
increase, then a decrease with a slope of about -1.5, which is steeper than that
expected from high field oxide film formation theory, suggesting that therepassivation of titanium is a combination of electrochemical and chemical
reactions. The repassivation current increases with increases in the applied
potential and addition of F- ions, while solution temperature does not influence therepassivation kinetics. The effect of F- ions on the repassivation kinetics can be
explained by localized pH changes caused by very rapid dissolution of titanium
when titanium was exposed to PBS solution.

182

ABSTRACTS of PUBLICATIONSCRGHUMetallization of Oxide / Hydroxide Film of Aluminum: thePalladium Activation Techniques,
Himendra Jha, Tatsuya Kikuchi, Masatoshi Sakairi, and Hideaki Takahashi,
J. Surf. Finsh. Soc. Jpn., 60, 208-212 (2009)

Palladium-activation-based techniques for area-selective microscale
metallization on porous oxide film of aluminum and complete metallization of theoxide/ hydroxide surface of aluminum are demonstrated. For area-selective
metallization, a porous anodic oxide film of aluminum was colored in an organic
dye solution containing small amounts of palladium acetate. It was thenhydrothermally sealed, thereby trapping the palladium acetate underneath the
newly formed crystalline hydroxide layer. Removal of the surface hydroxide layerusing a laser beam, exposes the palladium acetate, which also undergoes
photothermal decomposition and reduction to metallic palladium and acts as acatalytic center for subsequent electroless plating. Similarly, complete
metallization of the porous oxide and hydroxide of aluminum were performed byadsorbing palladium acetate onto the surface, followed by electroless nickel platingof the specimen. Here, palladium acetate (on the surface) was first reduced tometallic palladium by the hypophosphite that is present in electroless plating
solution, providing a catalytic center subsequent electroless nickel deposition.

183

ABSTRACTS of PUBLICATIONSCRGHUFormation of Three-dimensinal Micro-actuators with
Polypyrrole/Gold Bi-layer Structure
T. Kikuchi, S. Ueda, M. Ueda, M. Sakairi and H. Takahashi
J. Surf. Finsh. Soc. Jpn., 60, 335-341 (2009)

Three-dimensional micro-actuators consisting of a polypyrrole (PPy)/Au
bi-layer, were fabricated by Al anodizing, laser irradiation, and electrochemical
techniques. Aluminum specimens covered with porous type oxide films were
irradiated with a pulsed Nd-YAG laser to remove the oxide films locally. Then an
Au layer and a PPy layer were deposited at the area where the film had been
removed. Finally, the specimens were immersed in a NaOH solution afterconnection with or without a Pt plate to separate PPy/Au actuators from the Al
substrate and anodic oxide film. The PPy layer did not lose its electroconductivity
when the specimen was immersed in NaOH solution after connection with a Pt
plate, although the conductivity was lost after immersion of the specimen alone.
Immersion with the Pt connection suppressed the PPy reduction and enabled thefabrication of PPy/Au actuators. Three-dimensional PPy/Au bi-layer
micro-actuators were fabricated using column Al specimens. They are much more
flexible than PPy/Au/resin three-layer actuators described in a previous paper.
[Japanese]184

ABSTRACTS of PUBLICATIONS

CRGHUEffect of Aspect Ratio of Artificial Pits Formed on Al by PRM on
Localized Corrosion in Chloride Environments
M. Sakairi, A. Kageyama, Y. Kojima, Y. Oya and T. Kikuchi
ECS Trans., 16, 19-21 (2009)

A Photon Rupture Method (PRM focused pulsed Nd-YAG-laser
irradiation to remove materials) was applied to investigate effect of aspect ratio ofa pit on its growth rate and direction. It is possible to form artificial micro-pit on
aluminum by PRM, and the aspect ratio changes from 0.45 to 1.25 with irradiation
time. The current of formed micro-pit at constant potential increases with
irradiation time at constant potential. This result is good agreement with previous
pitting corrosion research results.

185

ABSTRACTS of PUBLICATIONSCRGHUElectrochemical Noise Analysis of 13 mass% Cr Stainless SteelHAZ by Solution Flow Type Micro-droplet Cell
- Effect of solution concentratinM. Sakairi, T. Nakayama, T. Kikuchi, S. Hashizume and K. Fushimi,
ECS Trans. 16, 281-290 (2009)

Low Carbon- 13 mass% Cr martensitic stainless steels have been widelyused for line pipe application because of their high strength and excellent corrosion
resistance in corrosive conditions. Newly developed solution flow typemicro-droplet cell was applied to investigate electrochemical behavior of heataffected zone (HAZ) of 13 mass% Cr stainless steel. This technique makes it
possible to measure electrochemical behavior of very narrow area of HAZ. Effectof solution pH and stress on corrosion potentials, and current at constant potential
for HAZ portion of welded joints were focused. The corrosion potential at HAZ
and base metal shows almost same tendency, however, current change shows clear
corrosion resistance difference at HAZ and base metal.

186

ABSTRACTS of PUBLICATIONSCRGHUThe Effect of Surface Condition and Solution Composition on theRepassivation Behavior of Titanium Studied by PRM in Vitro
M. Sakairi, H. Miyata, M. Kinjyo and T. Kikuchi
ECS Trans., 25, 37-45 (2009)

The effect of surface condition and solution composition on thelocalized repassivation kinetics of titanium was investigated by the photon rupture
method, PRM, and electrochemical techniques in aqueous electrolyte. The log I
vs. log t plots after laser beam irradiation showed a rapid increase, then a decrease
with a slope of about -1.5, which is steeper than that expected from high fieldoxide film formation theory, suggesting that the repassivation of titanium is acombination of electrochemical and chemical reactions. The repassivation current
increases with increases in the applied potential and suppressed withhydroxylapatite (HAp) coating, while solution compositions does not influence therepassivation kinetics. The effect of HAp coating on the repassivation kinetics canbe explained by localized pH changes caused by dissolution of HAp.

187

ABSTRACTS of PUBLICATIONS

CRGHUGalvanic Corrosion Behavior of 3003 Aluminum Alloy in Model
Tap Water
M.Sakairi, A. Kaneko,T. Kikuchi, Y. Seki, and D. Nagasawa
Proc. of Eurocorr2009, paper No. SS 17-O-7947 (2009)

Galvanic corrosion behavior of 3002 aluminum ally in model tap waters
was examined by electrochemical noise technique. In all model tap waters, after
specimen was connected to Pt cathode electrode, potential decrease withfluctuations and galvanic current increase with fluctuations. The current
fluctuations and potential fluctuations show good correlation. After theexperiments, there are corrosion products and micro pits were observed every
samples surface. Therefore, each fluctuation could be related to each event, birth,
propagation and death of pitting corrosion. The amplitude of both current andpotential fluctuations was suppressed by addition of Ca2+, Mg2+ and Cu2+. The total
amount of charge passed during the tests also decreases with addition of Ca2+,
Mg2+ and Cu2+.

188

ABSTRACTS of PUBLICATIONS

CRGHUEffect of PWHT on Electrochemical Behavior of Low C ‐ 13%Cr
Welded Joints with the Use of a Solution Flow Type
Micro-Droplet Cell
S. Hashizume, T. Nakayama, M. Sakairi and K. Fushimi
NACE 2009 Paper No.09089 ('2009)

Low Carbon-13%Cr martensitic stainless steels have been widely used
for line pipe application because of their high strength and excellent corrosion
resistance in corrosive conditions.
Recently, both laboratory and field
experiences related to cracking near fusion line of these steels weld joints in hotacid environments have been published. Electrochemical analysis of weld joints
is expected to be effective in understanding the crack mechanism. In this paper,electrochemical behavior of low C – 13%Cr weld joints with and without PWHT
was evaluated with the use of a solution flow type micro-droplet cell. In thisunique technique, a droplet of around 0.2mm diameter is used as anelectrochemical cell and it enables local electrochemical measurements. PWHT
leads to more noble and stable potential in HAZ compared to as-welded condition.
In the HAZ portion of the as-welded joint, Cr depleted zone was detected underwelding scale with the use of GDS (Glow Discharge Spectrometer). This can be
an initiation of SCC near girth welded joint in hot acid environment. The reason
why a polished specimen did not show any SCC is also given.

189

ABSTRACTS of PUBLICATIONSCRGHUHighly Uniform Aluminum Oxy-hydroxide Nanofiber from Porous
Anodic Alumina
H. Jha, T. Kikuchi, M. Sakairi and H. Takahashi
ECS Trans., 16, 2009 (2009)

A simple and effective method for the synthesis of aluminum
oxy-hydroxide nanofiber is demonstrated. In this method, porous anodic oxide filmof aluminum (porous anodic alumina) is used to synthesize the nanofibers, where it
acts both as a precursor as well as the template. Initially, the porous oxide film ishydrothermally treated for the formation of hydroxide (boehmite or
pseudoboehmite) inside the oxide pores, and then the porous oxide is selectively
etched from the film, using tri-sodium citrate solution, leaving the hydroxide intact.
The method results in highly uniform aluminum oxy-hydroxide nanofibers. The
size (diameter) of the nanofiber was controlled by controlling the size of the poresin the anodic oxide film.

190

ABSTRACTS of PUBLICATIONS

CRGHUEffect of the Electrodeposition Temperature on the
Cyclic-Oxidation Resistance of Ni Aluminide Containing Zr
Formed by Molten-Salt Electrodeposition
M. Fukumoto, T. Suzuki, M. Hara and T. Narita
Materials Transactions, 50, 335-340 (2009)
The effect of the Al electrodeposition temperature on the cyclicoxidation resistance of Ni aluminide containing Zr formed by molten salt
electrodeposition was investigated. Zr and Al were deposited by molten salt
electrolysis. For the sample treated with the Al deposition at 1073 K, a layer
consisting of Ni2Al3 was uniformly formed. On the other hand, for the sample
treated by Zr deposition, followed by Al deposition at 1073 K, a layer consisting of
Ni2Al3 and a Ni aluminide layer containing Zr on the Ni2Al3 layer were formed.
Furthermore, when the Al electrodeposition temperature was changed, theconcentration of Zr in the Ni aluminide layer containing Zr changed. When the Al
electrodeposition was carried out at 1153 and 1173 K, the Zr was scarcely
observed in the surface region of the Ni aluminide layer. The cyclic oxidation test
showed that for the sample treated with only the Al deposition and the sample
treated with the Zr deposition, followed by Al deposition at 1073 K, a mass
reduction due to scale exfoliation took place, whereas for the samples treated with
the Zr deposition, followed by Al deposition at 1153 and 1173 K, no mass
reduction was observed. For these samples, after the cyclic oxidation test, a scaleconsisting of α-Al2O3 adhering to the substrate was formed. Consequently, it was
found that the cyclic oxidation resistance of Ni was improved by Zr deposition,
followed by Al deposition at 1153 and 1173 K.

191

ABSTRACTS of PUBLICATIONSCRGHUExperimental and Simulation Study of Uphill Diffusion of Al in a
Pt-Coated γ-Ni-Al Model Alloy
B. Sundman, S. Ford, X-G. Lu, T. Narita, and D. Monceau
J. Phase Equilibria and Diffusion, 30, 602-607 (2009)
An experimental study of diffusion of Al, Ni, and Pt in a Pt-coatedbinary Ni-Al alloy has been made and compared with a computer simulation.
Assessed thermodynamic and kinetic descriptions have been used. Starting fromthe measured experimental concentration profiles after 1 h heat treatment at
1173 K the simulation is compared to the experimentally determined profiles after
11 h continuous heat treatment. The experimental finding that Al will diffuse
against its concentration gradient is explained by the strong lowering of thechemical potential by Pt. The simulation predicts that Al will reach a concentration
maximum at the surface, larger than its bulk composition.

192

ABSTRACTS of PUBLICATIONS

CRGHUDensity Functional Theory Study of Zinc Clusters
Kei Iokibe, Takeshi Sakamoto, Hiroto Tachikawa and Kazuhisa Azumi
J. Surface Finishing Soc. Japan, 60, 592-597 (2009)

Ab initio molecular orbital (MO) and density functional theory (DFT)
calculations were applied to zinc clusters comprising 2-192 atoms. The minimum
bonding length, average binding energy, and electron population of the 4p orbital(N4p) were evaluated as a function of the number of atoms (n) after optimization of
the cluster structure. The clusters show a drastic transition in their properties frommolecular to clusters at around n=4, and gradually exhibit bulk properties withincreasing n. Polarization of the clusters' electric charge was also
predicted—negative charging inside the cluster and positive charging at thesurface—attributable to nonuniform distribution of electrons belonging to theorbits of respective atoms. The highest occupied molecular orbital - lowest
unoccupied molecular orbital (HOMO-LUMO) transition energy gap withchanging n, the relation between the N4p value, the cluster stabilization energy, andthe influence of defects in the crystalline N4p are also discussed. (Japanese)

193

ABSTRACTS of PUBLICATIONSCRGHUDFT Calculation of Surface Diffusion of Zinc Adatom on Zinc
Crystal Surface
Kei Iokibe, Takeshi Sakamoto, Hiroto Tachikawa and Kazuhisa Azumi
J. Surface Finishing Soc. Japan, 60, 453-458 (2009)

Ab initio molecular orbital (MO) and density functional theory (DFT)
calculations were applied to surface diffusion analysis of a zinc adatom on a zinc(001) surface. An energetic contour map for surface diffusion of adatoms on
surfaces of terrace, step, and kink sites were drawn to evaluate the activationenergies for surface diffusion of each path. These sites' potential energies werehigher in the order of terrace, step, and kink. The activation energy for surface
diffusion on the terrace and through the step is considerably low. These results
were consistent with the general terrace–step–kink model proposed for epitaxial
growth during metal deposition. Validation of activation energy obtained by MO
calculation is discussed along with remaining problems of MO calculation applied
to electrochemical systems. (Japanese)

194

ABSTRACTS of PUBLICATIONSCRGHUDevelopment of a pH-Sensitive Film Using a Porous Anodic Oxide
Film on Al
F. Nishiyama, H. Konno, K. Azumi
J. Surface Finishing Soc. Japan, 60, 186-189 (2009)

A porous anodic oxide film formed on Al was developed as a new
pH-sensitive film. A porous anodic oxide film was immersed in an aqueous
solution containing a pH-indicator reagent and boiled to seal it in the film. Litmus,
bromthymol blue (BTB), and Congo red were used as pH-indicator reagents. The
film, containing litmus, changed color reversibly within 1 s as a function of the test
solution pH. The film showed superior durability in the solution at pH of 1−12
because of a stable boehmite layer covering the surface within that range. From theresponse of color change as a function of sealing time, it was inferred that the color
change occurred mostly at the film’s surface region. For example, the film
containing BTB prepared with long sealing time appeared to be green in an
alkaline solution because of mixing of blue at the surface and yellow inside thefilm. Optimization of film thickness, the choice of pH-indicator reagent, andsealing conditions are important to prepare a highly pH-sensitive film

195

ABSTRACTS of PUBLICATIONSCRGHUElectroless Ni-P Deposition on AZ91 D Magnesium Alloy
Prepared by Molybdate Chemical Conversion Coatings
H. H. Elsentriecy, K. Azumi
J. Electrochem. Soc., 156, D70-D77 (2009)

In this study, electroless nickel-phosphorus plating with good adhesion
strength was deposited on AZ91 D magnesium alloy prepared withenvironmentally acceptable molybdate chemical conversion coatings (Mocoatings). Energy dispersive X-ray spectroscopy (EDX) of Mo coatings revealed
that the conversion films were mainly composed of Mg2Mo3O11 particles. The Mo
coating showed a rough surface reflected by the non-uniform dissolution of a and bphases of the AZ91 D Mg alloy during the conversion process. Such a roughsurface provided excellent adhesion strength of the plating layer to the Mo
undercoating layer, reaching more than 18 MPa as measured by the pull-off
method due to the anchor effect. Scanning electron microscopy (SEM) results
showed that the plating layer over Mo coatings was also rough but compact andalmost pore-free. Corrosion tests using potentiodynamic polarization in 3.5 wt.%
NaCl aqueous solution indicated that the electroless Ni–P-plated AZ91 D Mg alloy
showed a significant improvement in corrosion resistance compared with thecorrosion resistance of uncoated specimens.

196

ABSTRACTS of PUBLICATIONS

CRGHU

Direct Reduction of Liquid V2O5 in Molten CaCl2
Y. Oka, and R.O. Suzuki
ECS Transaction, 16, 255-264 (2008)

An alternative process of the reduction of V2O5 was studied using
molten salt. It consists of thermochemical and electrochemical reactions in molten
CaCl2 + CaO. V2O5 is thermochemically reduced by Ca. The by-product CaO iselectrolyzed to the reductant Ca in the molten CaCl2. Liquid V2O5 was reduced to
vanadium metal through intermediate CaV2O4, and oxygen concentration was
1860ppm at minimum. By deoxidation of the sample with a smaller specificsurface area, the lowest oxygen concentration, 460 ppm, could be achieved． A
major component of ejected gas from the anode was CO2 at the initial stage andCO at the later stage. O2 gas was not detected because its concentration was lower
than detection limit.

197

ABSTRACTS of PUBLICATIONSCRGHUCalciothermic Reduction of TiCl4 Gas during the Electrolysis of
CaCl2 Melt
R.O. Suzuki and T. Naito
ECS Transaction, 16, 265-270 (2008)

The calciothermic reduction of TiCl4 gas was studied firstly by using
Ca-CaCl2 melt, to whose surface the gas was blown. The fine Ti particles settled
down in the crucible, when the concentration of dissolved Ca was greater than 2
mol% at 1173 K. When the concentration was less than 2mol%Ca, a part of TiCl4
gas was dissolved probably as TiCl3 or TiCl2 into the CaCl2 melt, and it
precipitated as the lower Ti oxides. When TiCl4 gas was blown to the molten CaCl2,
which was electrochemically decomposed into Cl2 gas at the carbon anode and Ca
at the Ti cathode, TiCl4 gas was reduced to the dendritic Ti on the cathode surface.
Because the electrolyzed Ca reacted preferentially with the oxide crucibles, mostof the oxygen ions combined with Ti(II) and Ti(III), and they formed TiO andTi2O3.

198

ABSTRACTS of PUBLICATIONS

CRGHUProduction Methods of Titanium at Present and in Future
R.O. Suzuki“Fundamentals and Current Applications of Titanium” Ed. by M. Niinomi, CMC
Press, Tokyo, 26-39 (2009).

The production methods for metallic titanium are reviewed. Only Kroll
method is taken as the industrial standard from various possible methods. Kroll
method bases on the chlorination of titanium oxide in the fluidized bed, distillationof TiCl4, magnesium reduction of TiCl4, and electrolysis of MgCl2. Although themodernized Kroll method can produced 10 ton per batch for several days, it is still
not comparable to the mass production of iron making. To establish a strong
industrial position of Ti production in the world, the Japanese companies try to
improve the processing and raw materials. These efforts are briefly reviewed.
Many ideas on new production method and their experimental efforts
are tentatively collected and introduced from the thermodynamical aspects. On therequirements from industrial situation and natural resouces, titanium oxides arecommonly taken as the starting materials. The assistance by the electrical energy is
indispensable, and the high temperature operation is needed to enhance theproduction rate. The molten salt technology or the gaseous chemical reactions cansolve these severe demands. FFC process and OS process are characteristic ideas
to face the molten salt electrolysis. Some reasonable solutions are now
approaching to the pilot plant level, but simultaneously they meet many serious
problems for industrialization. The wisdom and knowledge accumulated in thisfield are reviewed. (Japanese)

199

ABSTRACTS of PUBLICATIONSCRGHUCalciothermic Reduction and Simultaneous Electrolysis of CaO in
the Molten CaCl2
R.O. Suzuki
Proc. Processing Materials for Properties III Ed. by B. Mishra, A. Fuwa, and P.
Bhandhubanyong, ISBN:978-0-87339-727-8, TMS (The Minerals, Metals &Materials Society, USA), 387-392 (2008)
The combination of the calciothermic reduction and simultaneouselectrolysis of CaO in the molten CaCl2 (so-called OS process) was applied to themetal production of Ti and V. The pure Ti and V containing about 4000 mass ppm
oxygen was successfully obtained by controlling the supplied charge to form Ca
efficiently. The Ti-Al-V alloy powder was also produced from the mechanically
mixed oxides, and the distribution of metallic components could be homogenizedby sintering after removal of the solidified CaCl2.

200

ABSTRACTS of PUBLICATIONSCRGHUInfluence of Current Density to Direct Reduction of TiO2
in Molten CaCl2
K. Kobayashi, Y. Oka and R.O. Suzuki
Materials Transactions, 50, 2704-2708 (2009)

Titanium dioxide (TiO2) was successfully reduced at 1223 K by calcium,which was deposited due to the molten salt electrolysis of CaO dissolved in themolten CaCl2. The current density and the Ca concentration near the cathode werevaried by changing the electrodes’ surface areas and the distances between an
anode and cathode, respectively. At the initial stage of reduction, metallic Ti
powder with a lower oxygen concentration was obtained at a lower current density;in this case, most of the electrochemically deposited Ca was efficiently used for
reduction. Meanwhile, at the final stage of deoxidation, Ti powder with a much
lower oxygen concentration was obtained at a higher current density. In order toobtain metallic powder with a low oxygen concentration, the formed Ca should
penetrate the inner part of the sintered sample.

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CRGHU

Direct Metal Production from Oxides by Using Molten Salt
Electrolysis of CaO in CaCl2
R.O. Suzuki
Proc. Processing and Fabrication of Advanced Materials XVIII, Ed. by
M.Niinomii, M.Morinaga, M.Nakai, N.Bhatnagar and T.S.Srivatsan, 2, 701-710(2009)

Molten salt electrolysis of CaO dissolved in the CaCl2 melt can generate
the reactive Ca atmosphere near the cathode, which has a strong reducing ability
equivalent with pure Ca. When the oxide is set inside the basket-type cathode, it isreduced to the corresponding metal. The applied voltage should be controlled
between 1.6 and 3.2 V above the melting temperature of CaCl2 (1053K), when acarbon anode is used. The formed by-product CaO is removed as CO and CO2 gas
at the carbon anode. Within 3 hours we can obtain pure α-Ti from the starting TiO2
powder in CaCl2-0.5mol%CaO melt. As increasing the supplied charge, theresidual oxygen in Ti decreased.
This simple mechanism has been successfully applied for production of
12 kinds of metals such as Ti, Zr, V, Nb, Cr, Fe, etc. However, the rare earth
metals such as Y and Er could not be obtained due to thermodynamic limitation of
calciothermic reduction. MgO, In2O3 and SnO2 formed their metallic liquid.

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CRGHU

Direct Production of Ti-29Nb-13Ta-4.6Zr Biomedical Alloy from
Oxide Mixture in Molten CaCl2
S. Osaki, H. Sakai and R.O. Suzuki
Proc. Processing and Fabrication of Advanced Materials XVIII, Ed. by
M.Niinomii, M.Morinaga, M.Nakai, N.Bhatnagar and T.S.Srivatsan, 2, 815-824(2009)

Ti-29Nb-13Ta-4.6Zr(TNTZ) alloy was successfully produced byco-reduction of oxide mixture, which consisted of TiO2, Nb2O5, Ta2O5, and ZrO2.
This method uses high reducibility of Ca or Ca-condensed molten salt. Ca wasproduced by controlled-potential electrolysis of CaO in molten CaCl2 under 3.2V
at 1173K with carbon anode and Ti cathode. The supplied charge Q was varied in
the range of 50~400% of theoretical charge ( Q0) to generate the required amountof Ca to reduce the oxide mixture.
The oxygen concentration of the obtained powder sample decreased
monotonously as the supplied charge increased. 1.37 mass% oxygen could be
attained at Q/Q0 =165% and 1900 mass ppm at Q/Q0 =323%. X-ray diffraction
measurements identified the sample which has low oxygen concentration as the
mixture of Ti-based BCC solid solution and a small amount of HCP solid solution.
The electron probe microanalysis showed that the composition of this sample wasslightly different from the targeted composition due to difference of reduction rateof the component oxides. After sintering at 1300K for 54ks, the HCP phase
disappeared and the compositional homogeneity was improved within ±3.5mass%
to the targeted composition.

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CRGHU

Lithium Ion Insertion/Extraction Performance of Si/C/O
Composites Formed from Polyimides Containing Silicone
S. Saito, T. Kasashima, K. Fushimi, H. Konno
TANSO, 240, 207-212 (2009)
Si/C/O composites were formed by carbonization of Kapton type polyimide
films containing 0–10 at% Si. About 24 mass% of Si was present in the composite
derived from the polyimide containing 7 at% Si at 1350 ºC and, by 29Si MAS
NMR, they were mainly Si(O)4 type components around –110 ppm withunidentifiable components in a range of –100 to –20 ppm. This composite showed
the best performance of Li+ ion insertion/extraction: the coulomb efficiency was
nearly 100 % except for the 1st cycle and the extraction capacities were 648 mA h
g-1 after 10 cycles at 50 mA g-1 and 393 mA h g-1 after 100 cycles at 50 mA g-1,
and the latter was increased to ca. 470 mA h g-1 by preliminary cycles at low
current densities. After 10 cycles at 50 mA g-1 the components around –110 ppm
almost disappeared from NMR spectrum and a broad and noisy band was observedin a range of –100 to –50 ppm. Since sub-micrometer fused silica particles did notreact as the composites performed, the components around –110 ppm are notnecessary silica. The mechanism of reversible insertion/extraction of Li+ ion forthe composites was not completely clarified, but the results by cyclic voltammetry
and MAS NMR left room for doubt an alloying/dealloying mechanism between Si
and Li. (Japanese)204

ABSTRACTS of PUBLICATIONS

CRGHUPreparation of Boron-containing Carbons from Glucose-borate
Complexes and Their Capacitive Performance
T. Ito, M. Ushiro, K. Fushimi, K. Azumi, H. Konno
TANSO, 239, 156-161 (2009)
Hydrothemally synthesized glucose-borate complexes (mole ratio 1/1 and1/2) were carbonized at 800–1200 ºC for 1 h in argon, followed by boiling in waterto remove borate byproducts. Formed boron-containing carbons (B-carbons)contained 1–3.4 mass% boron and, by XPS, boron was present mainly as a form of
C-B-O bonding and not as the substituted boron. The specific surface area by N2
adsorption, SBET, was 850–1360 m2 g-1, and decreased with raising heat treatment
temperature. The 1/2 complex provided larger SBET than the 1/1 complex. Porewidth was less than 3 nm except for the products at 1200 ºC. The
cyclicvoltammograms (CVs) at 2 mV s-1 in 1 mol dm-3 Na2SO4 were rectangularand the specificcapacitance normalized by SBET, CA, was 0.05–0.1 F m-2, indicating
the electric double layer capacitance. In 1 mol dm-3 H2SO4, CVs showed broad
redox peaks in a potential range of 0–0.6 V vs. SCE and CA was 0.13–0.2 F m-2:
the pseudocapacitance is attributed to more than two types of oxygen-containing
functional groups and one of them might be =B-OH type. The electrodecapacitance, CM in F g-1, in H2SO4 solution was more than twice of the CM in the
Na2SO4 solution. It may be mainly due to the difference between Na+ and H+ ions,though a certain level of pseudocapacitance is contributing to CM. Carbons derived
from a mixture of poly(vinyl alcohol) and boric acid were SBET < 50 m2 g-1,
suggesting that the large SBET of B-carbon is owing to the thermal decomposition
behavior of glucose-borate complexes, which is different from the pore formation
mechanism of the MgO template method reported. (Japanese)

205

ABSTRACTS of PUBLICATIONSCRGHUAnodic Dissolution of Titanium in Chloride-containing Ethylene
Glycol Solution
K. Fushimi, H. Kondo, H. Konno
Electrochim. Acta, 55, 258-264 (2009)
Anodic dissolution behavior of titanium in chloride-containing ethylene
glycol was examined using a rotating disk electrode. A potential-independent
dissolution current flowed depending on the rotation speed, species andconcentration of chloride salts. In solutions with lower concentrations of chloride,a potential-independent current was controlled not only by the mass transfer
process but also by the charge transfer, and the kinetic-controlling current depends
on solution conductivity. In concentrated chloride solutions, the current wascontrolled only by mass transfer process and decreased with increase in chloride
concentration. A smaller current also flowed in a solution with a highconcentration of titanium species. These results indicated that the
diffusion-controlling species are titanium species, not chloride ions.
Electrochemical impedance spectroscopy revealed that a titanium chloride salt
layer, which maintains titanium species at a high concentration, accumulates a low
charge (~0.1 µF cm-2) and becomes thicker with increase in applied potential, isformed between the titanium substrate and diffusion layer during the masstransfer-controlling dissolution.

206

ABSTRACTS of PUBLICATIONSCRGHUCapacitance Behavior of Carbonaceous Materials Derived from
KAPTON Films Containing Small Amounts of Metallic Compounds
M. Ushiro, A. Yoneda, N. Iwasa, K. Fushimi, H. Konno
TANSO, 238, 121-125 (2009)
KAPTON films with and without adding small amounts of metallic
compounds (0.1~2 at% as metal) were carbonized at 800 ~ 1200 ºC for 1 h innitrogen and capacitance was measured in sulfate solutions by cyclic voltammetry.
Nitrogen containing carbons derived from the film without additives had low
specific surface area (SBET < 90 m2 g-1) and the capacitance (CT) was lower than 35
F g-1. The capacitance normalized by SBET (CSP), however, reached as high as 0.77
F m-2, and decreased with decreasing nitrogen content (WN), indicating
pseudocapacitance due to nitrogen. The correlation between CSP and a proportionof particular nitrogen species on surface was not observed. Except for silicone, theaddition of compounds of Fe(II), Co(II),Ni(II), and Ti(IV) increased SBET : SBET
increased with increasing amount of additives. The CSP value for the products at
850 ºC varied depending on the additives, and the products were grouped under a)nitrogen-containing carbons mainly showing pseudocapacitance due to nitrogen, b)
iron-containing carbons showing redox peaks, and c) carbons having relatively
high SBET (around 400 m2 g-1) and mainly showing the electric double layer
capacitance. (Japanese)207

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CRGHU

208

ABSTRACTS of PUBLICATIONS

CRGHUDepassivation-repassivation of Type-312L Stainless Steel in
NaCl Solution Investigated by the Micro-indentation
T. Yamamoto, K. Fushimi, M. Seo, S. Tsuri, T. Adachi, H. Habazaki
Corros. Sci., 51, 1545-1553 (2009)

Repassivation behavior of type-312L stainless steel containing 6% of
molybdenum was examined in NaCl solution using in situ micro-indentation
technique, together with type-304 and 316L stainless steels. High stability of thepassive film formed on the type-312L stainless steel was also examined by depth
profiling analysis of passive films using glow discharge optical emission
spectroscopy (GDOES). In 0.9 mol dm-3 NaCl solution at 296 K the type-304 and316L stainless steels are passive only up to 0.3 V (SHE), above which pitting
corrosion occurs. In contrast, no pitting corrosion occurs on type-312L stainlesssteel. Despite the significant difference of the pitting corrosion resistance, therepassivation kinetics of the three stainless steels, examined by micro-indentation
at 0.3 V (SHE), is similar. The presence of molybdenum in the stainless steel does
not influence the repassivation kinetics. The charge required to repassivate theruptured type-312L stainless steel surface increases approximately linearly with thepotential, even though the passivity-maintaining current increased markedly at
potentials close to the transpassive region. Repassivation occurs withoutaccompanying significant dissolution of steel, regardless of the stability of passive
state. Depth profiling analyses of the passive films on the type-312L stainlesssteels formed at several potentials revealed that molybdenum species enrich in theouter layer of the passive film, below which chromium-enriched layer is present.
The permeation of chloride ions may be impeded by the outer layer containing
molybdate, enhancing the resistance against the localized corrosion of thetype-312L stainless steel.

209

ABSTRACTS of PUBLICATIONSCRGHULimiting Current in a Flowing Electrolyte-type Droplet Cell
K. Fushimi, S. Yamamoto, H. Konno, H. Habazaki
ChemPhysChem, 10, 420-426 (2009)
Convective mass transfer in a flowing-electrolyte-type droplet cell (f-DC)
is investigated for quantitative analysis of an electrode process and precise
electrofabrication of microstructures using this device. The limiting current in the
f-DC was expressed theoretically and its practical equation is investigatedexperimentally by cyclic voltammetry in solutions containing a redox mediator.
The limiting-current equation in the f-DC derived experimentally could be
expressed as a sum of hydrodynamic and stagnant terms. The current derived fromthe latter term of the f-DC is ten times larger than that in a conventional stagnant
cell, thus indicating that the convective mass transfer in the cell would be changed
dramatically at a small volumetric flow rate.

210

ABSTRACTS of PUBLICATIONSCRGHUThe Effect of Metal Texture on Depassivation-repassivation
Behavior of Iron in Borate Buffer Solution Investigated byMicro-indentation
T. Yamamoto, K. Fushimi, H. Habazaki, H. Konno, S. MiuraECS transactions, 16, 133-140 (2009)
The effects of grain orientation and cold-rolling on the depassivation-repassivation behavior of polycrystalline irons were examined in pH8.4 borate
buffer solution using in-situ micro-indentation technique. The depassivation rateon the passive iron surface during the downward drive of the indenter (penetrationof an indenter tip into iron surface) depended on the grain orientation; the highest
rate was obtained on {100} surface, on which a possible main slip plane of {110}was normal to the surface. In contrast, the total electric charge required forrepassivation during the downward and subsequent upward drives was not
influenced by the grain orientation. The electric charge for repassivation wasstrongly influenced by the rolling reduction that changed the dislocation density at
the specimen surface. There was a linear correlation between the electric charge
normalized by residual dent area and the square root of the dislocation density.

211

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CRGHUDepassivation pH of Austenitic Stainless Steels in NaCl Aqueous
Solution
K. Fushimi, K. Takakura, H. Habazaki, H. Konno, K. Azumi, T. Tsuri
ECS transactions, 16, 291-296 (2009)
The combination of the potentiometric pH measurement and potentiostatic
polarization was carried out for the type-312L and 316L austenitic stainless steels
during decreasing pH by dropping hydrochloric acid in sodium chloride solution.
The acidification changed the surface condition of the austenitic stainless steels.
The significant acidity of the solution induced a rapid increase in the anodic
current passing through the steel at a critical pH, pHdepass. The value of pHdepass wasincreased by elevating the solution temperature or concentrating the chloride ionsin solution. In the potential–pHdepass diagram, the surface condition could beclassified into four domains; immunity, active, passive and transpassive/pitting
states. The boundary between the active and passive states was strongly dependent
on solution pH but independent of potential, indicating that the depassivation of
the steel surface proceeded with a chemical reaction participating protons rather
than the electrochemical one.

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