bluuebunny/crossref_metadata_2025 huggingface dataset:
Fabrication of Iron Oxide Nanostructures by Electron Beam-Induced Deposition
Authors: Shimojo Masayuki , Takeguchi Masaki , Mitsuishi Kazutaka , Tanaka M. , Furuya Kazuo
Published: March 2009

Electron beam induced-deposition (EBID) is a promising technique for fabricating
nanometer-sized structures in a position- and size-controlled manner. The resolution of EBID is now
reaching down to subnanometers. However, the deposits obtained by EBID contain a large amount of
carbon. Thus, carbon reduction techniques are needed. In this study, nanostructures, such as
nanowires, were fabricated by EBID using an iron pentacarbonyl precursor. Several techniques to
reduce carbon were applied, including post-deposition heat-treatments and the modification of
precursor. It was found that the post-deposition heat-treatment in air resulted in a formation of Fe2O3,
and that carbon-free Fe3O4 was formed by mixing a small amount of water vapor in the iron
pentacarbonyl precursor.
Precipitation Hardening in Fe-1.03%Cu Structural Steel
Authors: Ren Hui Ping , Wang Hai Yan , Liu Zong Chang , Chen Lin
Published: March 2009

The precipitation of copper during aging at 650oC within ferrite in high-purity
Fe-1.03wt%Cu steel was examined by transmission electron microscopy, and the influence of
precipitation particles on property of experimental steel was investigated. The microstructure and
the corresponding diffraction patterns of different zone axis were analyzed. Nano-scale copper-rich
clusters with B2-like structure and high density dislocation around precipitate was observed during
either solution treatment or aging. Nano-scale metastable precipitates and high density around them
were found to play the most important role for increasing steel strength.
Microstructure of Anisotropic Nd-Fe-B Film Magnets Prepared by Pulsed Laser Deposition
Authors: Ishimaru M. , Itakura M. , Kuwano N. , Sato S. , Nakano M. , Fukunaga H.
Published: March 2009

Microstructure of the anisotropic Nd-Fe-B thick-film magnets has been investigated by
transmission electron microscopy. Specimens of the thick-film magnets were prepared by the
high-speed pulsed laser deposition method with a substrate heating system. It was revealed that the
film deposited on a Ta substrate has a three-layer structure of Nd2Fe14B: The lower layer is composed
of isotropic grains about 50-300 nm in diameter, the middle one has a columnar structure of 1 3m in
height, and the upper one is again composed of small isotropic grains about several ten nm in
diameter. The three-layer-structure is explained to result from a partial recrystallization of
micro-crystalline Nd2Fe14B that are formed at the moment of deposition. In the middle layer, the
c-axis of columnar grains is fairly aligned in the direction perpendicular to the substrate surface. The
preferred orientation of c-axis produces the magnetic anisotropy of the thick-films.
Structural, Electrical and Magnetic Properties of Ni33Fe67 and Ni21Fe79 Films Deposited on SiO2/Si(100) at 633 K by DC Magnetron Co-Sputtering
Authors: Chen Xiao Bai , Qiu Hong , Wu Ping , Tian Yue
Published: March 2009

180nm-thick Ni33Fe67 and Ni21Fe79 films were deposited on SiO2/Si(100) substrates at 633
K by DC magnetron co-sputtering. Structural, electrical and magnetic properties of the films were
investigated using X-ray diffraction, field emission scanning electron microscopy, a four-point probe
technique and an alternating gradient magnetometer. The Ni21Fe79 film has a single bcc structure
whereas the Ni33Fe67 film is a fcc-bcc mixed phase. The films grow with granular grains. The grain
shape of the Ni21Fe79 film is triangular and rectangular. The Ni33Fe67 film consists of irregular shaped
grains and a few large triangular grains. The grain size of the Ni21Fe79 film is larger than that of the
Ni33Fe67 film. The resistivities of the Ni21Fe79 and Ni33Fe67 films are 1.82×10-63m and 1.09×10-63m.
The saturation magnetization of the Ni21Fe79 and Ni33Fe67 films are 1.09×106 A/m and 1.02×106 A/m.
The coercivity of the Ni21Fe79 and Ni33Fe67 films are 2.06×104 A/m and 8.84×103 A/m , respectively.
Performance of Low Resistivity Electrode Prepared by Electroless Plated for Amorphous Silicon Thin-Film Transistors
Authors: Tsay Chien Yie , Lin Chung Kwei , Lin Hong Ming , Chang Shih Chieh , Chung Bor Chuan
Published: March 2009

The TFTs array fabrication process for large-area TFT-LCD has been continuously
developed for simplifying processing steps, improving performance and reducing cost in the process
of mass production. In this study, the hydrogenated amorphous silicon (a-Si:H) TFTs with low
resistivity electrodes , silver thin films, were prepared by using the selective deposition method that
combined lift-off and electroless plated processes. This developed process can direct pattern the
electrode of transistor devices without the etching process and provide ease processing steps. The
as-deposited Ag films were annealed at 200 oC for 10 minutes under N2 atmosphere. The results
shows that the adhesion properties can be enhanced and the resistivity has been improved from 6.0
μ,-cm, significantly decrease by 35%, of as-deposited Ag films by annealed. The thickness of Ag
thin film is about 100 nm and the r. m. s roughness value is 1.54 nm. The a-Si:H TFT with Ag thin
films as source and drain electrodes had a field effect mobility of 0.18 cm2/Vs, a threshold voltage of
2.65 V, and an on/off ratio of 3×104.
Growth and its Properties of GaMnN Film Based on ECR-PEMOCVD
Authors: Qin Fu Wen , Wu Ai Min , He Huan , Jiang Xin , Xu Yin , Gu Biao
Published: March 2009

The DMS GaMnN film with certain concentration of Mn and good crystal qualities has
been successfully grown on the substrate of sapphire (α-Al2O3) by ECR-PEMOCVD. The graphs of
RHEED presented a clear spot-like lattice and the surface was not very glossy, which showed that the
GaMnN film was single crystalline and its growth model was three -dimensional island. XRD
analysis showed that the film was hexagonal structure with c -Axis oriented and the crystallinity was
very well. The AFM test result showed that the GaMnN films were composed of many submicron
grains with the same orientation. SQUID(superconducting quantum interference device)
measurement showed an apparent ferromagnetic hysteresis at room temperature, and the Curie
temperature of the film was about 400k.
High Rate Growth of Highly-Crystallized Ge Films on Quartz from VHF Inductively-Coupled Plasma of GeH4 + H2
Authors: Sakata Tsutomu , Makihara Katsunori , Deki Hidenori , Higashi Seiichiro , Miyazaki Seiichi
Published: March 2009

We have studied uniform growth of crystalline Ge films on quartz plate from VHF
(60MHz)-ICP of 10% GeH4 diluted with H2 in the temperature range from 150 to 350°C. By
optimizing total gas flow rate, gas pressure, VHF power and antenna-substrate distance, the growth
rate as high as 7.4nm/s was obtained at 150°C and increased gradually up to ~7.9nm/s at 350°C. The
crystallinity, which was evaluated by Raman scattering measurements as an integrated intensity ratio
of TO phonons in crystalline phase to those in disordered phase, reached a value as high as ~93 % at
350°C, but degraded down to 64% at 150°C as a result of the formation of a 60~70nm-thick
amorphous incubation (A. I.) layer on quartz. By applying a two-step deposition method at 150°C, in
which the GeH4 concentration was selected to be 0.6% for the crystalline nucleation in the first 10s
deposition, being as thin as 10nm in thickness, and then changed to 10% GeH4 for the high rate
growth, the crystallinity was improved to 78% with keeping an effective growth rate as high as
7.5nm/s, because of a significant increase in the growth rate after the crystalline nucleation.
Characterization of Electronic Charged States of Nickel Silicide Nanodots Using AFM/ Kelvin Probe Technique
Authors: Nishihara Ryousuke , Makihara Katsunori , Kawaguchi Yoshihiro , Ikeda Mitsuhisa , Murakami Hideki , Higashi Seiichiro , Miyazaki Seiichi
Published: March 2009

We have formed high density nanodots of nickel silicide (NiSi) on ultrathin SiO2 and
characterized their electronic charged states by using an AFM/Kelvin probe technique. Si
quantum dots (Si-QDs) with an areal dot density of ~2.5x1011cm-2 were self-assembled on
~3.6nm-thick thermally-grown SiO2 by controlling the early stages of LPCVD using pure SiH4
gas. Subsequently, electron beam evaporation of Ni was carried out as thin as ~1.7nm in
equivalent thickness at room temperature and followed by 300°C anneal for 5min in vacuum.
XPS and AFM measurements confirm the formation of NiSi dots with an average dot height of
~8nm. After removal of Ni residue on SiO2 by a dilute HCl solution, bias conditions required
for electron charging to NiSi dots were compared with those to pure Si-QDs dots and Ni dots.
The surface potential changes stepwise with respect to the tip bias due to multistep electron
injection and extraction of NiSi nanodots. In addition, it is confirmed that charge retention
characteristics of NiSi dots are superior to those of Si-QDs with the almost same size.
Effect of Reducing Thickness of TiN Buffer Layers on Epitaxial Growth of GaN Layes
Authors: Ito Kazuhiro , Uchida Yu , Lee Sang Jin , Tsukimoto Susumu , Ikemoto Yuhei , Hirata Koji , Uemura Toshiya , Murakami Masanori
Published: March 2009

We investigated effect of reducing thickness of TiN buffer layers on growth of the smooth
GaN layers. The sputtered TiN layers with thicknesses in the range of 2 to 100 nm were deposited on
sapphire substrates. The sputtered TiN layers were exposed NH3 + H2 mixed gas atmosphere at about
1000°C to enrich nitrogen concentration of the layers. GaN layers were deposited on the
nitrogen-enriched TiN layer using a MOCVD method. Average grain size of the nitrogen-enriched
TiN layer was minimized at the thickness of 5 nm. In the initial stages of GaN growth, density of GaN
hexagons grown on the 5nm-thick TiN layers was the highest. The 2μm-thick GaN layers grown on
the 5nm-thick TiN layers exhibited the smoothest surface. Thus, the 5nm thickness is believed to be
the best thickness for the smooth GaN growth on the sapphire/TiN substrates.
XRR and SAXS Study of Hydrogenated Amorphous Silicon Oxycarbide (a-SiOC:H) Films
Authors: Swain Bibhu P.
Published: March 2009

Thin films of hydrogenated silicon-oxycarbide (a-SiOCx:H) have largely replaced pure silicon oxide
films as back end of line (BEOL) processing in Ultra Large Scale Integrate Circuit (ULSI). A single
chamber system for hot wire chemical vapor deposition (HWCVD) was employed to deposit
different films of a-SiOCx:H with 0.5 < x < 0.8. All films were characterized by infrared
spectroscopy and X-ray photoelectron spectroscopy (XPS) to determine the stoichiometry and the
presence of various bonding configurations of constituent atoms. We used X-ray reflectivity (XRR)
and Small angle X- ray scattering (SAXS) to determine the porosity and inhomogeneities
(clustering) in the films.
The Production and Elevated Temperature Properties of Ca65Mg15Zn20 Bulk Metallic Glass
Authors: Laws Kevin J. , Gun B. , Ferry Michael
Published: March 2009

Ca65Mg15Zn20 bulk metallic glass samples of dimensions 3.15 × 7 × 125 mm were prepared
using an inverted low-pressure die-casting technique. It was found that charge temperature, and
injection pressure were important parameters for controlling the length, porosity and degree of
crystallinity in the as-cast samples. A processing map was generated illustrating the optimum casting
temperature and pressure range for generating the highest quality castings. These samples were
ground into tensile samples in compliance with ASTM E8-04 and deformed in the supercooled liquid
(SCL) region (105 to 135 °C) at constant strain rates from 10-3 to 10-4 s-1. Reported are the effects of
these parameters on the deformation behaviour of the Ca65Mg15Zn20 BMG.
Viscous Flow Behaviors of Supercooled Liquids of Pre-Annealed Zr55Cu30Al10Ni5 Bulk Metallic Glasses
Authors: Yamasaki Tohru , Maeda S. , Kikuchi Takeyuki , Fukami Takeshi , Yokoyama Yoshihiko , Yamamoto Tokujiro , Kimura Hisamichi , Inoue Akihisa
Published: March 2009

Viscous flow behavior in supercooled liquid region of as-cast and pre-annealed
Zr55Cu30Al10Ni5 bulk metallic glasses has been examined by using a penetration viscometer under
high-speed heating rate of 20, 200 and 400 °C/min. Applied load for the cylindrical-shaped penetration
indenter with a diameter of 1 mm was varied from 0.049 N to 0.294 N. Viscosity was quite
independent of these applied loads. By pre-annealing the bulk metallic glasses at 400 °C, the density
of the glasses increased, while the viscosity and the activation energy for viscous flow in their
soopercooled liquid decreased with the pre-annealing treatments. Corresponding measurements of the
differential thermal calorimetry (DSC) have been also done.
Ultrasonic Attenuation Properties of Glassy Alloys in Views of Complex Viscoelasticity
Authors: Fukuhara Mikio , Zhang Wei , Louzguine-Luzgin Dmitri V. , Inoue Akihisa
Published: March 2009

Using ultrasonics, acoustic characteristics of Pd40Cu30P20, Zr55Cu30Al10Ni5, Zr65Pd12.5Ni10Al7.5
Cu5, Cu55Zr30Ti10Pd5, Cu45Zr20Hf25Ag10 and Ti41.5Cu42.5Ni7.5Hf5Zr2.5Sn1 glassy alloys were examined
in terms of complex elasticity. The order of bulk modulus (K), Lamè parameter (λ ), Young (E ) and
shear (G ) moduli of the glassy alloys is monopoltical character of glassy alloys, except for polymers
and rubbers. For metals and alloys, ceramics, polymers and glassy alloys, Poison’s ratio correlates
well to ratio G /K. Complex elasticity indicates that viscoelasticity of the glassy alloys is
predominated by volumetric motion.
Origin of Different Dependence of Apparent Glass-Forming Ability on Casting-Atmosphere-Pressure in Zr-Al-Ni-Cu-Pd Alloy System
Authors: Setyawan Albertus D. , Kato Hidemi , Saida Junji , Inoue Akihisa
Published: March 2009

A Zr65Al7.5Ni10Cu17.5-xPdx (x=0-17.5 at. %) alloy system is found to exhibit a different
dependence of glass-forming ability (GFA) on atmosphere-pressure during mold casting process.
High-Pd alloys (x=7.5-17.5) show a remarkable increase of critical size for glass formation (dc) as
casting-atmosphere (Ar) pressure varies from vacuum to ambient. No significant change of dc,
however, is observed in low-Pd alloys (x=0-5) despite the variation in atmosphere pressure. The
origin of the phenomenon is unveiled by correlating the cooling characteristic during mold casting
and on-cooling phase transformation characteristic of the alloy system.
Solid Solution Formation Criteria for High Entropy Alloys
Authors: Zhang Yong , Zhou Yun Jun
Published: March 2009

The solid solution formation criteria for the equi-atomic ratio alloys were discussed. It is
found that higher entropy of mixing (Smix>1.61R), less atomic size difference (δ<4.6), and near zero
of the absolute value of the enthalpy of mixing (-2.685δ-2.54<Hmix <-1.28δ+5.44 KJ/mol) facilitate
the formation of solid solution for the multi-principle components equi-atomic alloys.
Glass Forming Ability and Thermal Properties of a Cu-Based Bulk Metallic Glass Microalloyed with Silicon
Authors: Jang Jason S.C. , Huang Y.C. , Lee C.H. , Lee I.S. , Chang L.J.
Published: March 2009

The (Cu42Zr42Al8Ag8)100-xSix amorphous alloy rods, x =0 to 1, with 3 mm in diameter
were prepared by Cu-mold drop casting method. The glass forming ability, thermal properties and
microstructure evolution was studied by differential scanning calorimetry (DSC), and X-ray
diffractometry (XRD). The XRD result reveals that these as-quenched (Cu42Zr42Al8Ag8)100-xSix
alloy rods exhibit a broaden diffraction pattern of amorphous phase. The crystallization temperature
and GFA (glass forming ability) of (Cu42Zr42Al8Ag8)100-xSix alloys increase with the silicon
additions. The highest Trg (0.59) and γ value (0.405) occurred at the (Cu42Zr42Al8Ag8)99.75Si0.25 and
(Cu42Zr42Al8Ag8)99.5Si0.5 alloy. In addition, both of the activation energy of crystallization and the
incubation time of isothermal annealing for these (Cu42Zr42Al8Ag8)100-xSix alloys indicates that the
(Cu42Zr42Al8Ag8)99.25Si0.75 alloy posses the best thermal stability among the (Cu42Zr42Al8Ag8)100-xSix
alloy system.
Structural Stability and Elasticity in Zr-Based Bulk Metallic Glasses
Authors: Zhang Shuo , Ichitsubo T. , Yokoyama Yoshihiko , Miyagi K. , Matsubara Eiichiro
Published: March 2009

The structure, thermal stability and elasticity of Zr50Cu40Al10 bulk metallic glass (BMG)
have been investigated with reference to Zr70Cu30 and Zr70Cu20Al10 amorphous alloys. The thermal
stability of Zr50Cu40Al10 is significantly enhanced in comparison compared with those of the others.
The large total coordination numbers more than 11 around all constituent elements are observed in
Zr50Cu40Al10. A change of the bulk modulus in the crystallization is extremely small in Zr50Cu40Al10.
The present experimental results indicate that atoms in the Zr50Cu40Al10 glass are closely packed
and its microstructure is fairly uniform. This results in the much higher thermal stability of
Zr50Cu40Al10.
A Study of Testing the Nanocatalyst Decomposition Efficiency of Methanol (CH3OH) and Ethanol (C2H6O)
Authors: Jwo Ching Song , Chen Chien Chih , Chang Ho , Chen Sih Li , Lin Chi Hsiang
Published: March 2009

This research carries out an inexpensive, rapid and novel exercise, which is applied to
perform the photocatalyst decomposition effectiveness of Methanol and Ethanol in gaseous form.
The major devices of this applicable measurement developed by this practice are only utilizing
ultraviolet-visible spectrophotometer and quartz cuvette, and the experimental procedures are
straightforward and speedy. In the conduct experiments, Methanol and Ethanol with a specific
concentration is initially injected into an enclosed quartz cuvette. Then the cuvette is put in
ultraviolet- visible spectrophotometer to measure the Methanol and Ethanol concentration, so as to
obtain an unique UV absorbance spectrum at its particular concentration. In the conduct
experiments of measuring photocatalyst decomposition efficiency, the self-made (SANSS)
nanocatalyst TiO2 is initially coated in the quartz plate, and put into the quartz. Then a specific
concentration of methanol alcohol and ethanol is injected into the quartz cuvette under the UV
irradiation exposure, so as to carry out photodecomposition of Methanol and Ethanol experiment.
After that, the cuvettes are then put into the ultraviolet-visible spectrophotometer for measuring the
absorbance intensity of UV spectrums in order to produce degradation chart. The preliminary
results point out that the self-made nanocatalyst TiO2 has exceptionally outstanding decomposition
efficiency which further points out the fact that, when UV irradiation for 60minutes, the gaseous
Methanol can be reduced to 3.8% of the original sample, and the gaseous Ethanol can be reduced to
6% of the original sample. But when exercising with commercial nanocatalyst TiO2 to undergo the
same process exactly under the same circumstances, the residue gaseous concentration can only be
reduced to 17% and 16% of the gaseous Methanol and Ethanol original sample.
Synthesis and Consolidation of Nano-Sized NiCo Powder by Powder Technology Rout
Authors: Daoush W.M.
Published: March 2009

Nano sized Co-20wt%Ni composite powder was synthesized by electroless chemical reduction method using
metallic salt precursors and hypophosphite as a reducing agent in alkaline tartarate bath as a complexing agent. The
synthesized powder provide better sinterability, mechanical, electrical and magnetic properties with homogeneous
microstructure. The nano-sized powder could be obtained, which have the average particle size of 40 nm, with a saturation
magnetization (Bs ) of 97.95 which was increased by heat treatments of powder in hydrogen to 127 emu/g due to the exclusion
of the precipitated phosphrous in the composite powder. The powder underwent cold compaction at 600 Mpa and sintering at
1050 oC for 30 min. The saturation induction for the sintered material of 149.3 emu/g higher than the synthesized powder and
has electrical resistivity value of 7.6 μcm.
Preparation and Characterization of Natural Hydroxyapatite: A Comparative Study of Bovine Bone Hydroxyapatite and Hydroxyapatite from Calcite
Authors: Herliansyah M.K. , Nasution D.A. , Bin Abdul Shukor Mohd Hamdi , Ide-Ektessabi A. , Wildan Muhammad Waziz , Tontowi A.E.
Published: March 2009

The production of natural hydroxyapatite (HAp) specifically from cortical bovine bones
and natural calcite was studied in this paper. Bovine hydroxyapatite (BHA) was produced from
bovine bone in bulk form by de-fatting continued with calcination at 900°C. Natural calcite
hydroxyapatite (CHA) was produced by hydrothermal method. It was confirmed from XRD, FTIR,
and SEM results that HA have been successfully produced from natural sources like bulk bovine
bone and natural calcite. The results also show that the crystallinity of BHA is higher than CHA,
matching with the hardness test results of sintered BHA and CHA.
Stress-Induced Lattice Transit Behavior in a Cold-Rolled Cu-Al-Mn Two-Way Shape Memory Alloy
Authors: Wang Ji Jie , Wu B.L. , Huang Z.W. , Cui Tong , Wang Yan Dong , Kainuma Ryosuke , Ishida Kiyohito
Published: March 2009

The effect of cold rolling on two-way shape memory was investigated by x-ray diffraction
technique and TEM in a Cu-18Al-10.5Mn (at.%) alloy. Cold rolling leads to a preferred orientation
distribution on the stress-induced martensite with 6M-structure, which leads to the dependence of
two-way shape memory on the specimen directions. The relationship of stress state and anisotropy of
6M-structured martensite lattice inside cold rolling deforming region is elucidated through analyzing
the deformation process-related variant selection according to original grain orientation.
Polarisation Behaviour of 316L Stainless Steel in Cell Culture Environment
Authors: Hiromoto Sachiko
Published: March 2009

Understanding of interaction reactions between materials and tissue in the body is
necessary for the success of implant devices. Impedance and polarisation properties at the interface
on 316L stainless steel and pure Ti under cell culture environment of fibroblast L929 or with collagen
coating were examined. Limitation of mass diffusion at the interface by cell bodies and extracellular
matrix is probably a corrosion factor of the presence of cells, which causes the decrease of
protectiveness of passive film on 316L steel. Surface composition of 316L steel and Ti formed with
L929 was compared with that formed in human body. Similar elements were detected on the surface
formed in both the environments. The precipitated sulphur on the surface formed under cell culture
and in the human body appears to be originated from proteins that might be produced by cells.
Mechanical Behaviors of Ti-29Nb-13Ta-4.6Zr-XO for Biomedical Applications Subjected to Cold Working and Various Heat Treatments
Authors: Niinomi Mitsuo , Akahori Toshikazu , Nakai Masaaki , Ishikawa Hiroshi , Ogawa Michiharu
Published: March 2009

The effect of oxygen content on aging behavior and invar characteristics of
Ti-29Nb-13Ta-4.6Zr (TNTZ) were investigated. The age hardening of TNTZ aged at 573 K and 723
K is enhanced with the oxygen content. The ω phase precipitates and grows from early stage of
aging in TNTZ regardless of the oxygen content when aged at 573 K. The lath-like shape α phase
precipitated in TNTZ aged at 723 K increases in size with the oxygen content. The elastic modulus
increases with the oxygen content and aging. The ω phase increase the elastic modulus to a greater
extent than the increase due to the α phase. The tensile strength increases with the oxygen content
and aging, while the elongation decreases. TNTZ with oxygen content of 0.1 mass% exhibits
invar-like characteristics through severe cold working. A higher oxygen content suppresses the
invar-like characteristics of TNTZ.
Effects of Cross-Linkage and Hydroxyl Groups on Bonding Strength between Titanium and Segmented Polyurethane through 3-(Trimethoxysilyl) Propyl Methacrylate
Authors: Sakamoto Harumi , Hirohashi Yohei , Doi Hisashi , Noda Kazuhiko , Hanawa Takao
Published: March 2009

To create a new material with good biocompatibility and high mechanical strength for
artificial organs, titanium (Ti) and segmented polyurethane (SPU) were bonded through
3-(trimethoxysilyl) propyl methacrylate (γ-MPS), and specify causes governing the bonding strength
of Ti/γ-MPS/SPU interface. The number of cross-links of SPU and the concentration of active
hydroxyl groups on the surface oxide film of Ti were controlled by UV-irradaiton and hydrogen
peroxide immersion. The number of cross-links of SPU was measured by differential scanning
calorimetry (DSC) and the concentration of the active hydroxyl groups was also determined using a
zinc-complex substitution technique. Consequently, Ti/γ-MPS/SPU shear bonding stress was
increased with the increase of the number of cross-links of SPU. In addition, the increase of
cross-links in SPU also improved the Ti/γ-MPS/SPU shear bonding stress.
Change in Tensile and Fatigue Properties of Biomedical Ti-29Nb-13Ta-4.6Zr Alloy Fabricated by Various Processings
Authors: Akahori Toshikazu , Niinomi Mitsuo , Nakai Masaaki , Ogawa Michiharu
Published: March 2009

The tensile and plain fatigue properties of the β-type titanium alloy, Ti-29Nb-13Ta-4.6Zr
alloy (TNTZ), which was subjected to various thermomechanical treatments, and cast TNTZ were
investigated in order to judge its potential for biomedical and dental applications.
The tensile strengths of TNTZ aged after solution treatment and that aged after cold rolling decrease
with an increase in the aging temperature; however, their elongation exhibits an opposite trend.
TNTZ composed of the ω phase or the ω and α phases in the β phase exhibits a tensile strength of
about 1000 MPa or more. The tensile properties of the cast TNTZ with and without a surface
reaction layer is are not significantly different, and are almost identcal to those of as-solutionized
TNTZ. The plain fatigue strengths of TNTZ aged after solution treatment and those of TNTZ aged
after cold rolling increase with the aging temperature. In particular, TNTZ aged at 723 K after cold
rolling exhibits the highest fatigue strength in both the low- and high-cycle fatigue life regions.
Further, the plain fatigue limit, which is about 770 MPa, is nearly equal to that of hot-rolled
Ti-6Al-4V ELI alloy subjected to aging after solution treatment; Ti-6Al-4V ELI alloy is a
representative α+β-type titanium alloy for biomedical applications. The plain fatigue strength of
cast TNTZ with a surface reaction layer is considerably less than that of the as-cold-rolled and
as-solutionized TNTZ. Consequently, in the low-fatigue life region, the fatigue crack easily occurs
at the surface reaction layer, which is brittle, and in the high-fatigue life region, the fatigue crack
occurs at the sites of casting defects (shrinkage). The fatigue limits range from 180 MPa to 200
MPa.
Hard-Ceramic Layer Formed on Ti-29Nb-13Ta-4.6Zr and Ti-6Al-4V ELI during Gas Nitriding
Authors: Nakai Masaaki , Niinomi Mitsuo , Akahori Toshikazu , Ohtsu Naofumi , Nishimura H. , Toda Hiroyuki , Fukui Hisao , Ogawa Michiharu
Published: March 2009

The surface of Ti-29Nb-13Ta-4.6Zr (TNTZ) subjected to gas nitriding at 1023–1223 K
was investigated in comparison with the conventional biomedical titanium alloy, Ti-6Al-4V ELI
(Ti64). After gas nitriding, the microstructures near the surface of these alloys were observed by
optical microscopy, X-ray diffraction, Auger electron spectroscopy, and X-ray photoelectron
spectroscopy. In both alloys, two titanium nitrides (TiN and Ti2N) are formed and the α phase
precipitated by gas nitriding. Furthermore, oxygen impurity in the gas nitriding atmosphere reacts
with the titanium nitrides; thus, TiO2 is formed at the outermost titanium nitride layer. The surface
hardening was also evaluated by Vickers hardness measurement. The Vickers hardness near the
surface of TNTZ and Ti64 increases significantly by gas nitriding.
Hydrogen Storage Properties of FCC Type Mg-Transition Metal Hydrides Prepared by GPa High Pressure Method
Authors: Takasaki Tomoaki , Kyoi Daisuke , Kitamura Naoyuki , Tanase Shigeo , Sakai Tetsuo
Published: March 2009

Hydrogenation / dehydrogenation properties of a series of ternary face centered cubic
(FCC) hydrides “Mg7MHx” (M = Sc, Ti, V, Zr, Nb, Hf and Ta), which were prepared by a
high-pressure technique, were investigated. Differential scanning calorimeter (DSC) measurements
under hydrogen atmosphere revealed that these hydrides exhibited reversible hydrogen releasing and
re-storing properties at around 600 and 560 K, respectively. These releasing temperatures are lower
by 100 ~ 120 K than that of MgH2. Furthermore, pressure-composition isotherm at 523 K shows that
these FCC hydrides release 3.8 - 5 wt. % hydrogens.
Comparison between Mg/Cu Super-Laminates and Mg2Cu Powder in Microstructure and Hydrogen Storage Properties
Authors: Tanaka Koji , Takeichi Nobuhiko , Tanaka Hideaki , Kuriyama Nobuhiro , Ueda Tamotsu T. , Tsukahara Makoto , Miyamura Hiroshi , Kikuchi Shiomi
Published: March 2009

Super-laminates have been attracting attention since co-authors Ueda et al. reported that
Mg/Cu super-laminates showed reversible hydrogenation and dehydrogenation at 473K. The
Mg/Cu super-laminates were prepared by a repetitive fold and roll method. Initial activation at 573
K led the super-laminates to absorb hydrogen at 473K. TEM observations of micro/nano-structures
in the super-laminates and Mg2Cu powder were performed in order to clarify the process of
hydrogenation and dehydrogenation at 473K. The as-rolled Mg/Cu super-laminates have laminated
structures in size of sub-micrometer thickness composed of Mg and Cu layers with dense lattice
defects. The super-laminates after initial activation keep laminated structure and have uniformly
distributed pores with a sub-micrometer diameter. It is considered that these micro/nano-structures
of Mg/Cu super-laminates lead to lower dehydrogenation temperature and better kinetics.
Synergetic Effect of Oxides on Hydrogen Reaction Kinetics of Magnesium Hydride
Authors: Patah Aep , Takasaki Akito , Szmyd Janusz S.
Published: March 2009

The kinetics of hydrogen reaction (absorption and desorption) on the MgH2 have been
reported to be improved significantly by addition of transition metal oxides as catalysts. Among the
oxides reported previously, Cr2O3 seems to improve hydrogen absorption kinetics and Nb2O5 for
desorption kinetics. The catalytic effect of addition of more than one oxide, however, has not been
reported yet. We investigated the hydrogen reaction kinetics of ball milled MgH2 powders added
with either Cr2O3 or ZnO together with Nb2O5. In absorption reaction, the hydrogen contents
reached 6 wt% and 5.3 wt% in 5 min for the powders added with 1 mol% ZnO + 1 mol% Nb2O5
and with 1 mol% Cr2O3 + 1 mol% Nb2O5, respectively. Those powders desorbed hydrogen up to
about 4.5 wt% in 20 min. The significant improvement was not expected if one of the oxides was
added separately. The combination of two kinds of oxides might play an important role for
improvement of reaction kinetics.
In Situ High-Resolution Observation for Decomposition of NaAlH4
Authors: Kawasaki Hiroshi , Ohnuki Somei , Suda Takanori , Hashimoto Naoyuki , Kojima Yoshitsugu
Published: March 2009

NaAlH4 has a theoretical hydrogen capacity of 5.6 wt. % with two-step reaction, and the
control of the reaction temperature and reversibility is a critical issue for onboard application. To
clarify nano-structural details of decomposition of NaAlH4, the in-situ annealing experiment was
carried out in a high resolution microscope. It was confirmed that NaAlH4 decomposed at between
200 and 300°C, resulted in formation of many gas bubbles at interface between the particle and
oxide film. A reactive intermediate, Na3AlH6, may decompose in this temperature range. Sodium
alanate particle was originally agglomeration of small nano-sized crystal with the size of 10 – 20
nm, and the crystal grain grew to 110 nm in diameter after completing decomposition at around
400°C. This is the first step for examination of the microstructural response of catalysts on
hydrogen storage materials.
Preparation and Hydrogen Storage Properties of Mg-Ni-B BCC Alloys
Authors: Shao Huai Yu , Asano Kohta , Enoki Hirotoshi , Akiba Etsuo
Published: March 2009

Mg-Ni-B system alloys were prepared by the mechanical alloying (MA) method. Body
centered cubic (BCC) structure alloys are obtained in some of the Mg-Ni-B compositions after the
starting mixtures of raw elements were ball milled for 200 h. Mg50Ni45B5 and Mg48Ni48B4 alloys
after ball milling are with single BCC structure, which is confirmed by electron diffraction patterns.
From the results of X-ray diffraction and transmission electron microscope, the crystallite size of
the alloys is calculated into nanometer scale. Mg50Ni45B5 and Mg48Ni48B4 BCC alloys can absorb
hydrogen at 373 K with higher rate than Mg50Ni50 alloy prepared in the same conditions. And these
two samples can reach a hydrogen absorption capacity of 1.94 and 1.93 mass%, respectively at 373
K without any activation process.
Long Term Creep Properties of a Die-Cast Mg-Al-Ca Alloy
Authors: Terada Yoshihiro , Sato Tatsuo
Published: March 2009

Creep rupture tests were performed for a die-cast Mg-Al-Ca alloy AX52 (X
representing calcium) at 29 kinds of creep conditions in the temperature range between 423 and 498
K. The creep curve for the alloy is characterized by a minimum in the creep rate followed by an
accelerating stage. The minimum creep rate (ε& m) and the creep rupture life (trup) follow the
phenomenological Monkman-Grant relationship; trup = C0 /ε& m
m. It is found for the AX52 die-cast
alloy that the exponent m is unity and the constant C0 is 2.0 x 10-2, independent of creep testing
temperature. The values of m and C0 are compared with those for another die-cast magnesium
alloys. The value m=1 is generally detected for die-cast magnesium alloys. On the contrary, the
value of C0 sensitively depends on alloy composition, which is reduced with increasing the
concentration of alloying elements such as Al, Zn and Ca.
Thermoelectric Power Hydrogen Sensors for Reversible Hydrogen Storage Materials
Authors: Lasseigne-Jackson A.N. , Zamarron A. , Ashraf I. , Mishra Brajendra , Olson D.L.
Published: March 2009

Thermoelectric power has demonstrated a capability for rapid hydrogen assessment and
can achieve the equivalent of the pressure-composition-temperature (activity) diagram. Effective
use of hydrogen storage materials occurs in the alpha+beta two-phase region of the activity
diagram. A thorough assessment of the content of each phase in this two-phase region can optimize
the performance of hydrogen storage materials. The use of thermoelectric power measurements as
a hydrogen sensor for reversible batteries is discussed.
Influence of Density on the Compressive Properties in Porous Copper Produced by Spacer Method
Authors: Hakamada Masataka , Asao Yuuki , Kuromura Tetsumune , Chen You Qing , Kusuda Hiromu , Mabuchi Mamoru
Published: March 2009

Porous copper specimens with relative densities of 0.22–0.96 were produced by spacer
method and their compressive properties were investigated. In the low relative density range (relative
density < 0.5–0.6), porous copper showed a density exponent n of 2.3, where n represents the relative
density dependence of yield strength. In this range, the bending and buckling of cell walls and the
formation of macroscopic deformation bands were observed. On the other hand, porous copper with a
higher relative density (0.5–0.6 < relative density < 0.9–1) had an n value of approximately 1, where
the dominant deformation mode of cell walls was yielding and no clear deformation band was
observed. Also, in the highest relative density range (relative density is very close to 1), the
compressive properties degraded markedly with decreasing density, indicating that stress
concentration around the minimal pores occurred in this density range.
Structural Analysis on Anisotropic Deformation Properties of Highly Porous Aluminum Material
Authors: Asahina Tadashi , Jeon Insu , Katou Kiyotaka , Sonoda Tsutomu
Published: March 2009

The cell-structure of highly porous aluminum material prepared by foaming of aluminum
alloy melt with titanium hydride was investigated nondestructively with fine-focus X-ray 3D-CT at
several interrupt steps during slow compressive deformation. The foamed highly porous aluminum
has anisotropic shape of each cell inevitably because of gravity force during solidification of foamed
material and mechanical properties especially the dependence on the deformation direction of highly
porous aluminum is analyzed well from the size and shape of each void composing the porous
material. The statistic anisotropic distribution of these form factors such as three axial lengths and
directions at the time of ellipsoidal approximation of each cell was found to be less important to
improve the mechanical properties of this type of material.
Fundamental Research on Fatigue Properties of Closed-Packed Hexagonal Lattice Metal under Biaxial Stress
Authors: Ito Yasumi , Shimamoto Akira , Nemoto Tetsuya , Koide Kazuharu , Inamori Akira , Yanai Shyuichi , Matsuura Hiroyuki
Published: March 2009

Assisted living instruments and medical implants, such as wheelchairs and joint prostheses
are usually subjected to biaxial or three-axial stresses instead of uniaxial stress. So, authors already
developed a servo biaxial fatigue-testing machine, and clarified about the performance evaluation.
Moreover, closed-packed hexagonal lattice metal, such as magnesium and titanium, is frequently used
for assisted living instruments or medical implants. In this research, fatigue crack propagation tests of
magnesium alloy AZ31B and pure titanium TP340C were conducted under conditions of biaxial and
uniaxial loading by using a cruciform specimen in a bi-axial fatigue machine, in order to investigate
the effect of non-singular stress cycling on the fatigue crack growth properties ⊿K-da/dN. From these
comprehensive experiments, in the magnesium alloy, the re-markable effect was found in the specific
biaxial load stress ratio on ⊿K-da/dN relation. When biaxial load stress ratio was 0.5, it turned out
that the fatigue crack propagation rate of a magnesium alloy becomes very slow. On the other hand, in
the titanium, it was confirmed that there is a little influence of a biaxial load stress ratio on ⊿KⅠ
-da/dN relation.
Fabrication of Low Temperature Foaming Glass Materials Using Hydrothermal Treatment
Authors: Yoshikawa Takeshi , Sato Shinsuke , Tanaka Toshihiro
Published: March 2009

In order to prepare the functional porous glasses, fabrication of foaming glass materials was
achieved utilizing the hydrothermal treatment. In the present paper, SiO2-Na2O-B2O3 glass was
hydrated by the hydrothermal hot pressing of the glass powder mixed with pure water under the
condition of loading pressure of 40 MPa and heating up to 523K. The hydrothermally treated glass
contained 10.8 mass% of water. By heating up to 473 K, it started to foam by releasing water and
the porous structure was obtained. The minimum apparent density was obtained to be 0.25 g /cm3
after the heat treatment at 673 K for 300 s. It was clarified that the prepared hydrated glass with the
hydrothermal treatment would be promising for fabricating the porous glass materials by firing at
low temperature.
Oxidation Behavior of Cu Nanoparticles and Formation of Hollow Cu2O Spheres
Authors: Nakamura Ryusuke , Tokozakura Daisuke , Lee Jung Goo , Mori Hirotaro , Nakajima Hideo
Published: March 2009

Oxidation behavior of Cu nanoparticles in the formation process of hollow Cu2O spheres
was investigated by TEM. The thickness of Cu2O layers on Cu nanoparticles oxidized at 323 K in air
was measured as a function of oxidation time. At the initial stage of oxidation until the oxide film
with 2.5 nm in thickness is formed, the thickness of oxide films on Cu nanoparticles with the diameter
of 10, 20 and 35 nm shows a nearly equal value regardless of diameter of Cu. After the formation of
2.5 nm layer, however, the growth rate of the oxide films on smaller nanoparticles becomes slower
than that on larger nanoparticles. This result suggests that the voids formed at the Cu/Cu2O interface
prevent Cu atoms from diffusing outward across the interface because the volume ratio of voids to
inner Cu in smaller nanoparticles is much larger than that in larger nanoparticles.
The Production Practice on Digesting Solid Wastes in Blended Material for Sinter
Authors: Xia Shi Rong , Sun Hong Zhen
Published: March 2009

To comprehensive utilize the large amount of solid wastes from the production process,
Iron making plant gradually increases solid wastes proportion in blended material for sinter by a
series of process improvement and equipment upgrading. These approaches optimize technology
index of blended material and provide refined material for blast furnace. Thus it creates considerable
economic and social benefits the environmental via economizing the resources and reducing the
environmental burden.
Precipitation Hardening Behavior of Al-4wt.%Cu Alloys Aged at Low Temperature under High Magnetic Field
Authors: Cui Li Ying , Li Xiao Na , Qi Min
Published: March 2009

A 10-T magnetic field was introduced to investigate precipitation behavior of
Al-4wt.%Cu alloys during short time aging at 130°C. DSC, Vickers micro-hardness tests, EPMA
and TEM were used to characterize aging process. The results show that high magnetic field
improves the diffusion of Cu atom, lowers the stability of G.P.( I )zone and speeds up its solution,
and lowers the precipitation temperature of the phases, thus accelerates the ageing course during the
early stage at low temperature. Furthermore the high magnetic field has influence on the size of the
θ″-phase. The micro-hardness of the field-treated specimen is always higher than the non-field ones,
which indicates the high magnetic field strengthens the hardening effect.
Formation of Al-Based Intermetallic Compound under Ion Implantation at Lower Temperature
Authors: Kinoshita Hisao , Sakaguch N. , Watanabe S. , Takahashil H. , Kawai Masayoshi , Gotthardt Rolf , Phillipp F.
Published: March 2009

The formation process of intermetallic compound under Ni+ion implantation into pure Al
was studied at lower temperature below room temperature. Ion implantation was carried out using
250KeV ion accelerator. Cascade damage was introduced Ni+ions implantation at 223K without
new phase nucleation. However, when Ni+ions were implanted at room temperature, the grown
larger plate-like phases were observed during implantation up to 1x1017 Ni+/cm2. Ni concentration
in Al matrix and newly formed phase were 0.3-0.5 and 8.5-13.3at%,respectively. It was identified
that the formed phases were close to the ordered orthorhombic structure of Al3Ni type. It was also
confirmed from observation with high resolution HVEM that these phases grew with continuous ion
implantation. Thus it was clarified that cascades act as preferential nucleation site for intermetallic
compound, and the phases nucleated at cascades coalesce in the growth process of each phase
during continuous implantation through ion irradiation enhanced diffusion.
Formation of Defect Clusters in SrTiO3 Crystals Implanted with Xenon Ions
Authors: Song Ming Hui , Guo Xing Jian , Ishikawa Nobuhiro , Takeguchi Masaki , Mitsuishi Kazutaka , Furuya Kazuo
Published: March 2009

SrTiO3 crystals were implanted with 100 keV xenon (Xe+) ions at 673 or 1073 K up to
2.0 × 1020 ions m−2. Defect clusters formed in the ion-implanted samples were investigated with
conventional and high-resolution transmission electron microscopy. Nanometer-sized clusters were
formed in the samples. The clusters grew large in size after post-implantation annealing and with
increasing the implantation dose. The clusters were faceted with {100}, or {110} of SrTiO3. Though
the nano-sized clusters were expected to contain Xe atoms, they were not in crystalline state. The
results suggest that even if the clusters contain Xe atoms, they also contain other point defects such
as vacancies.
EXAFS Study on Irradiated ODS Ferritic Steel
Authors: Pouchon Manuel A. , Chen Jia Chao , Degueldre Claude , Froideval Annick , Emerich Hermann , Van Beek Wouter
Published: March 2009

The commercial material PM2000 is investigated as a representative for the material class
of Oxide Dispersion Strengthened (ODS) steels. ODS steels are envisaged as substance of structural
components in Very High Temperature Reactors (VHTR). The VHTR concept is considered by the
Generation IV International Forum, an initiative researching the next generation of nuclear power
plants. The chosen ODS is mainly used for non-nuclear applications. In order to justify the
applicability of this material within a neutron irradiative environment, the evolution of radiation
damage must be investigated. PM2000 samples are therefore exposed to 4He2+ irradiation at different
temperatures. The potential structural change is measured as a function of the radiation parameters,
using Extended X-Ray Absorption Fine Structure (EXAFS) spectroscopy on the yttrium K-edge and
on the iron K-edge. A degradation of the dispersoids or the steel matrix would show the limitation of
this material candidate.
Effects of Neutron Irradiation and Thermal Aging on Mechanical Properties of ODS Ferritic Steels for Advanced Nuclear Systems
Authors: Kasada Ryuta , Cho Hang Sik , Okuda Naoyuki , Kimura Akihiko
Published: March 2009

Effects of neutron irradiation and thermal aging on the tensile properties and Charpy
impact properties of oxide dispersion strengthened (ODS) ferritic steels for advanced nuclear systems
were investigated and discussed with the results of microstructural observation. After the neutron
irradiation in JMTR, significant hardening after irradiation at 290 and 400 °C as well as thermal aging
at 500 °C, while no effect was observed after irradiation at 600 °C. While the irradiation hardening
was not accompanied by a reduction of total elongation in tensile tests, Charpy impact energy at room
temperature was reduced after the irradiation. The hardening after the irradiation at 400 °C and the
aging at 500 °C was probably due to the formation of Cr-rich phases. The irradiation hardening
observed in the ODS ferritic steels irradiated at 290 °C was well explained by the formation of
dislocation loops.
Numerical Simulation on the Liquid Metal Flow of the Acceleration Phase in the Shot Sleeve of Cold Chamber Die Casting Process
Authors: Yang Jie , Yuan Lang , Xiong Shou Mei , Liu Bai Cheng
Published: March 2009

Slow shot velocity and its acceleration phase in the shot sleeve have great influence on the
flow pattern of the liquid metal in the shot sleeve. In this paper, a three-dimensional model based on
the SOLA-VOF algorithm was developed and used to simulate the flow of melt in the shot sleeve. The
mathematical model was verified by water analog experiments with constant plunger velocities.
Based on numerical simulation results, the influences of the plunger acceleration on the wave profile
of the liquid metal in the shot sleeve under different fill ratios and sleeve diameters were investigated.
The results indicated that in order to avoid air entrapment in the shot sleeve, the optimal acceleration
value to the critical slow shot velocity increases with the increase of the fill ratio, and the range of
suitable acceleration becomes wider as well. With the same fill ratio, the value of suitable acceleration
rises as the plunger diameter increases.
Simulation of Cold Ring Rolling Based on Rate Dependent Crystal Plasticity
Authors: Li Hong Wei , Yang He , Sun Zhi Chao , Wang M. , Li Lan Yun
Published: March 2009

Material behaviors of anisotropy and rate sensitivity affect cold ring rolling greatly. So, a
self-developed incremental model of rate dependent crystal plasticity (RDCP) is utilized to forecast
the deformation characteristics of this forming process based on a 3D FE model under
ABAQUS/Explicit environment. The results show that the model of RDCP captures material
behaviors of anisotropy and rate sensitivity better in this forming process by the comparison with the
model of J2 plasticity; with the decrease of rate sensitivity coefficient, the forming process becomes
more unstable with smaller rolling force and growth in ring radial direction; with the increase of feed
rate of idle roll, the deformation of ring becomes more even while the rolling force becomes larger.