bluuebunny/crossref_metadata_2025 huggingface dataset:
Using Friction Stir Processing to Fabricate Mg Based Composites with Nano Fillers
Authors: Lee C.J. , Huang J.C. , Hsieh P.L.
Published: March 2009

There have been numerous methods in fabricating particulate reinforced metallic matrix composites, including stir casting, squeeze casting, spray forming, powder metallurgy, and mechanical alloying. In this paper, one solid state processing technique, friction stir processing, is applied to incorporate 5-15 vol% nano-sized ceramic particles SiO2 into the AZ61 Mg alloy matrix to form bulk composites, using the characteristic rotating downward and circular material flow around
the stir pin. The upper working FSP temperature is controlled to less than 400oC in order to avoid chemical reaction. The fixed pin tool is 6 mm in diameter and 6 mm in length, with a shoulder diameter of 18 mm and a 3o tilt angle. The advancing speed of the rotating pin is kept constant to be 45 mm/min, with rotational speed of the pin from 800 rpm (rotation per min), resulting in a strain rate around 101 s-1. After one-pass FSP, the particle dispersion within the central cross-sectional area of
the onion ring regions, measuring nearly 6 mm in diameter, was macroscopically uniform. However, the observed particle size is frequently 0.5-5 µm, much larger than the individual SiO2 size (~20 nm), suggesting the clustering of nano particles. The situation after two FSP passes, with an opposite FSP
direction for the second pass, appear to be further improved. Electron microscopy characterizations reveal that the aggregating particles were seen to vary from 10 to 1000 nm in size. Some of the large particles, 1-5 µm in diameter, were identified to be the Mn bearing dispersoids (e.g. Al4Mn) by the SEM-EDS. The average grain sizes of the composites with 5-15 vol% SiO2 varied within 00.5-2 µm, and the composites double the hardness as compared with the as-received AZ61 cast billet.
Throwing Power during Electrophoretic Deposition
Authors: Anné Guy , Neirinck Bram , Vanmeensel Kim , Van der Biest Omer , Vleugels Jef
Published: March 2009

The deposit can induce an extra potential drop near the electrode, depending on the
suspension composition. This can result in a levelling off of the deposition rate in a constant-voltage
deposition process. The magnitude of the extra voltage drop determines the uniformity of the
deposit as function of the uniformity of the electric field present at the deposition electrode. It was
experimentally proven that a uniform Al2O3 coating thickness was obtained in a non-homogeneous
electrical field in ethanol with addition of HNO3, while the coating thickness varied uniformly with
the E-field strength for a MEK with n-butylamine based suspension. The uniformity of the coating
deposited from these suspensions was related to the measured potential drop over the deposit during
electrophoretic deposition.
Electrophoresis in Membrane Separation Processes: From Lab to Field Scale Experiments
Authors: Falk G.
Published: March 2009

In this paper results of electrophoretically activated processes for domestic wastewater treatment in
lab and field scale experiments are presented.
The principal mechanisms of non-membrane and membrane based electrokinetic solid liquid
separation by electrophoresis are described. In the case of non-membrane based electrokinetic
wastewater treatment a modular processing scheme is suggested in order to achieve economically
and ecologically suitable processing conditions based on colloidal wastewater characteristics.
In the case of membrane based electrokinetic waste water treatment an effective anti-membrane
fouling process is designed controlled by colloidal characteristics of the wastewater, especially zetapotential,
as well as external field parameters and microfiltration module geometries.
The specific energy input of the membrane based and non-membrane based electrophoretic waste
water treatment methodologies are compared and future perspectives of electrokinetic activated
waste water purification processes are proposed.
FEM Simulation of the Residual Stress in the Machined Surface Layer for High-Speed Machining
Authors: Wang Su Yu , Ai Xing , Zhao Jun , Lv Z.J.
Published: March 2009

An orthogonal cutting model was presented to simulate high-speed machining (HSM)
process based on metal cutting theory and finite element method (FEM). The residual stresses in the
machined surface layer were obtained with various cutting speeds using finite element simulation.
The variations of residual stresses in the cutting direction and beneath the workpiece surface were
studied. It is shown that the thermal load produced at higher cutting speed is the primary factor
affecting the residual stress in the machined surface layer.
Selective Laser Sintering of Multi-Component Cu-Based Alloy for Creating Three-Dimensional Metal Parts
Authors: Gu D.D. , Shen Yi Fu
Published: March 2009

Selective laser sintering (SLS) of a multi-component Cu-based alloy, which consisted of
a mixture of Cu, CuSn, and CuP powder, was successfully processed. The XRD, SEM, and EDX
analysis shows that the bonding mechanism of this process is liquid phase sintering with partial
melting of the powder occurred. The CuSn powder with lower melting point acts as the binder,
while the Cu powder with higher melting point acts as the structural metal. The element phosphorus
acts as a fluxing agent to prevent the Cu particles form oxidation. The distribution of phosphorus
shows higher concentration at grain boundaries due to low solubility of P in Cu. A case study on
SLS of this powder system to fabricate a gear was carried out. The relative density of 82% and
radial dimension error of 1.9% were achieved.
Study on Mechanical Properties of Cermet Materials Fabricated from Ternary Boride Cladding on Both Sides Surface of Steel Substrate
Authors: Huang Wei Ling , Liu Fu Tian , Huang Chuan Zhen , Li Zhao Qian , Dong F.
Published: March 2009

Using Mo powder, B-Fe alloy powder and Fe powder as raw materials, with proper
forming additives, the slurry was prepared. The green body was formed by spray method on both
sides of 16Mn and Q235 steel substrate separately. Both side ternary boride based cermet cladding
materials FC-V16Mn and FC-VCuQ235 were fabricated by liquid phase sintering technology. Both
materials have high hardness, bending strength and good corrosion resistance.
Monitoring of End-Mill Behavior with Its Projection Image
Authors: Zuo Dun Wen , Kawano Yoshihiro
Published: March 2009

End mills with small diameter have found their wide application with the development of
high-speed cutting. It becomes more and more important to develop effective methods to monitor
and control the milling process with small end mills. In this paper, a measuring system of projection
image for small end mills is introduced, and the application of the projection image to monitor the
behavior of the end mill is discussed. It is found that for static state of the end mill, the
measurement accuracy can be easily controlled within 1 μm. When the end mill rotates, it is not so
difficult to control the accuracy within 3 μm. By using of the change in image width, the radial wear
of end mill can be predicted. On the other hand, if the centre shift of the image is pre-measured, the
deflection of the end mill during cutting can be predicted.
Study of Inhibition to Leaching of Cobalt from Cemented Carbide Tools
Authors: Zhang Hao Qiang , Jia Xiao Ming , Gao Y. , Hou Suo Xia
Published: March 2009

Cutting fluid is the essential material in metal cutting process. This paper mainly studies the influence of TEA-containing solution on cobalt leaching from cemented carbide tools and the leaching mechanism, and then identifies the effective inhibitor. The results are as follows: (1) TEA additive can make cobalt leach from cemented carbide tools. (2) Addictive of triethanolamine oleate in the solution can obviously inhibit the leaching of cobalt from cemented carbide tools and there exists the best proportion. (3) The mixture of triethanolamine oleate and borax has the best inhibition function. So it can conclude: The mixture of triethanolamine oleate and borax can obviously reduce the leaching of cobalt from the cemented carbide tools, which improves the working life of the cutter and reduces the danger of the fluid to human body.
Research on Theory and Technique of Point Form Grinding for Quadratic Surface Flank of Twist Drill
Authors: Li Chao , Wang Min , Zuo Dun Wen
Published: March 2009

A new principle and technology of point form grinding for quadratic surface flank of twist
drill was investigated. It broke through the traditional straight-line generator grinding method for the
conical and the spiral drills. The principle of implementation mechanism was given in the paper. The
trueness and feasibility of the method had been approved in the experiments, and the quadratic surface
twist drill such as hyperboloid, ellipsoid and hyperboloid-ellipsoid compound flank had been grinded
on the mechanism.
Nano-SiC Particles Reinforced Plasma Sprayed WC-Co Coating by Laser Melting Process
Authors: Zhao J.F. , Li Yong , Wang L.
Published: March 2009

The laser-melting process of SiC nano-particles coated on the plasma sprayed WC-Co coating was performed. The SiC nanocomposite coating was prepared, and the microstructure and the mechanical properties of it were investigated. After laser irradiated, parts of nano SiC particles are turned into the inner of coating with the nano-micro composite structure. The being of SiC nano-particles in coating brings the better fine microstructure and the higher densification. The wear-resistant property and the corrosion-resistant property of the coating with SiC nano-particles are improved more than the coatings prepared by laser melting process without the SiC nano-particles.
Experimental Study on Ultrasonic Grinding and Polishing for Large-Scale Silicon Wafer
Authors: Bleck Wolfgang , Wang Ming , Zuo Dun Wen , Wang Min , Rui Yan Nian
Published: March 2009

How to improve the surface quality of large-scale silicon wafer in the ultra-precision
grinding process, will always be the most important issue discussed by the silicon wafer
manufacturer. In this paper, the advantage of ultrasonic grinding is being explored. These
advantages included small macro grinding force, grinding stress, low grinding heat, which will
reduce the surface damage. Combined with relatively abrasive, a large-scale silicon wafer can be
processed. Through the study, an experimental system for ultrasonic grinding of large-scale silicon
wafer is designed. The working parameter is optimized and the expected result is obtained, which
searches a new way for the practical implementation.
A New Magnetic Polishing Liquid (MPL) for Precision Surface Finishing
Authors: Jiang J. , Wu Yong Bo , Wang Xu Yue , Kato M.
Published: March 2009

This paper presents a new magnetic polishing liquid (MPL) produced by mixing sub-micron or micron order abrasive particles into a magnetic compound fluid (MCF) and its fundamental performance in surface finishing. MCF is an intelligent fluid, which is developed by mixing a magnetic fluid (MF) and a Magneto-rheological fluid (MRF) into a solvent, and hence reacting upon magnetic fields. In the present work, seven kinds of kerosene-based MPLs were prepared. The hydrodynamic characteristics of MPLs such as the viscosities under different magnetic fields were investigated. The obtained result indicated that the viscosity increases with the growing of the magnetic field and that the type of MPL affects greatly the viscosity. This phenomenon was discussed by observing the magnetic clusters formed in MPL. It was observed that the magnetic clusters are distributed along the magnetic fluxes. An experimental result indicated that the surface roughness varies with polishing time and gets smallest at a certain value of magnetic field strength.
Mechanochemical Polishing of Single Crystal Diamond with Mixture of Oxidizing Agents
Authors: Wang Cheng Yong , Chen C. , Song Yue Xian
Published: March 2009

In order to achieve the smooth surface of diamond, several kinds of mixture oxidizing agents have been used to polish the single crystal diamond by a designed polishing apparatus. The existing of graphite and amorphous carbon has been found in the surface of diamond after polishing. The mechanochemical actions of oxidizing agents and the polishing iron plate have been proved. The mixture of oxidizing agents can decrease the polishing temperature so that the super-smooth surface of single crystal diamond can be achieved at lower temperature. The method provided is benefit not only to simplify polishing device and control the polishing process, but also to improve the removal rate and surface roughness.
Analysis and Application of Acoustic Emission Signals in Accurate Grinding Machining
Authors: Gong Ya Dong , Li H. , Yu Tian Biao , Wang Wan Shan
Published: March 2009

This paper analyzes Acoustic Emission (AE) signals in accurate-grinding machining, and
influencing factors related in the process. It is indicated that there is favorable corresponding
relationship between AE signals with different characteristic parameters and accurate-grinding
status, which can be used to monitor the accurate-grinding machining and grinding quality.
Liquid-Phase Sintered Silicon Carbide with Aluminum Nitride and Rare-Earth Oxide Additives
Authors: Hotta Mikinori , Enomoto Naoya , Hojo Junichi
Published: March 2009

SiC was sintered with AlN and Y2O3 as sintering additives by spark plasma sintering (SPS).
Using nano-sized β-SiC powder as the starting material, the sintered density reached about 95% of
theoretical at 1800-2000oC for 10min. The β to α phase transformation of SiC was not found by XRD.
The secondary phase such as Y2O3 decreased as the firing temperature was elevated, and β-SiC
monophase was identified at 2000oC. It seems that the residual intergranular glassy phase is present
between the SiC grains. Significant SiC grain growth was observed at 1800-1900oC by SEM. The
grain size decreased with increasing amount of AlN additive. The maximum value of flexural strength
of the sample reached approximately 800MPa. These results are discussed on the basis of the
liquid-phase sintering mechanism in AlN-Y2O3 and Al2O3-Y2O3 systems.
Thermodynamical Calculations and Experimental Confirmation about the Mg-Al-Spinel Reaction Path in the Sol-Gel-Process
Authors: Wunderlich Wilfried , Vishista Krupathi , Gnanam Francis D. , Jayaseelan Daniel Doni
Published: March 2009

The aim of this research is, to clarify which route the sol-gel-process is taking in the case of
a Al-Mg-spinel slurry, in particular, whether the hydrolysis reaction or the spinel formation is faster
and which of the intermediate hydroxide phases Al(OH)3, and Mg(OH)2, or MgO and Al2O3 or
MgAl2O4H2O are formed during the spinel formation. The spinel-alloy was produced using the
polymeric route during wet chemical processing. Aluminium-isopropoxide was hydrolyzed in order
to form the boehmite-sol and then the same amount of magnesia was added and mixed. This sol
precipitated as boehmite (AlOOH) and brucite (Mg(OH)2) after ageing for 12h as confirmed by
differential thermal analysis (DTA), and differential thermal gravity (DTG) measurements. After that,
the powders were subsequently annealed at 900oC for 3h in air and observed by TEM. Calculations
using thermodynamic enthalpy data are in good agreement with the experiments and can be used to
predict reaction paths in other system as well.
Centrifugal Sintering
Authors: Kinemuchi Yoshiaki , Morimitsu H. , Ishiguro H. , Uchimura Shoji , Watari Koji
Published: March 2009

Co-firing of multiple materials results in the formation of internal stress due to the
difference in shrinkage behavior. This internal stress causes retardation of sintering, crack formation
and/or de-lamination at the interface. To reduce internal stress in layered structures, homogeneous
pressing via centrifuge has been attempted. The effect of centrifugal pressing was demonstrated by
film sintering, in which crack suppression and void removal by the present process were revealed.
Owing to the homogeneous microstructure, the thermal stability of the film was significantly
improved.
Fracture Toughness of Fibrous Si3N4 Monolithic Ceramics
Authors: Guo Hai , Yoon Dae Hyun , Shin Dong Woo
Published: March 2009

Fibrous Si3N4 monolithic ceramics with a hexagonal cell were fabricated in the preferred
orientation. The densified Si3N4 fibrous monolithic showed fracture toughness of 17 MPam1/2. An
application of SiC whisker as reinforcement exhibited higher fracture toughness (24 MPam1/2).
The influences of fiber diameter and reinforcement on the fracture toughness of these fibrous
monolithic ceramics were studied in details.
The Change of Mechanical Properties for Anodic Aluminum Oxide by Heat Treatment
Authors: Park D.J. , Kim S.H. , Lee J.H. , Lee Seong Hee , Choa Yong Ho
Published: March 2009

Anodic aluminum oxide (AAO) was prepared in three types of aqueous solutions with various applied voltage. The mechanical property of AAO prepared in different electrolyte was investigated and hardness was increased on account of the increase of the thickness between pores. The mechanical property and microstructure change of AAO prepared in oxalic acid at 40V was investigated by heat treatment. AAO prepared in oxalic acid at 40V was transformed from amorphous to crystalline phase by heat treatment above 800oC and hardness was increased about 2.6 times with increase of heat treatment temperature.
Rolling Life Properties of Ceramic Bearings in Water
Authors: Yamamoto Toyohisa , Ito Hiroyuki , Niizeki Shin , Matsunaga Shigeki
Published: March 2009

Rolling life properties of ceramic bearings in water were studied. In addition, we
investigated the influence of ceramics, such as Si3N4, ZrO2 and SiC, on rolling life of bearings in
water. All ceramic bearings possess from 15 to 70 times longer rolling life than all AISI440C steel
bearings. All Si3N4 and ZrO2 ceramic bearings possess from 3.5 to 5 times longer rolling life than
hybrid bearings. Rolling life of all SiC ceramic bearings is approximately the same as hybrid bearings.
Rolling life of ceramic bearings in water is mainly due to propagation of cracks, pitting and flaking.
Hydrothermal Preparation and Characterization of Barium Titanate Powders
Authors: Lu Chung Hsin , Wu Po Chi
Published: March 2009

Barium titanate powders were synthesized via a hydrothermal process at 120-180 using
titanium oxide powder with different particle sizes as starting materials in this study. When
micron-sized titanium oxide was used, pure perovskite phase was not formed because of the
insufficient chemical reactivity of titanium oxide. However, as nano-sized titanium oxide was utilized,
pure barium titanate was obtained after the hydrothermal process was performed at 180 oC. The
effects of sintering temperature on the dielectric properties of barium titanate were also investigated.
Densified ceramics with high dielectric constants were obtained after sintering at 1200oC.
Comparison of Water Vapor Corrosion Behaviors of Ln2Si2O7 (Ln=Yb and Lu) and ASiO4 (A=Ti, Zr and Hf) EBC's
Authors: Ueno Shunkichi , Jayaseelan Daniel Doni , Kita Hideki , Ohji Tatsuki , Lin Hua Tay
Published: March 2009

The corrosion behaviors of Ln2Si2O7 (Ln=Yb and Lu) and ASiO4 (A=Ti, Zr and Hf) EBC's
were examined at 1500oC in water vapor environment. These oxides were coated on silicon nitride
specimens by oxidation-bonded reaction sintering technique. Among Ln2Si2O7 system, though the
thermal expansion coefficient of Yb2Si2O7 phase is closer to silicon nitride than that of Lu2Si2O7
phase, the corrosion resistance of silicon nitride with Lu2Si2O7 EBC was higher than that of Yb2Si2O7
EBC sample. In these EBC materials, boundary silica phase was easily corroded by water vapor.
Among ASiO4 system, though the corrosion rate of HfSiO4 bulk was larger than that of ZrSiO4 and
TiSiO4 phases, the oxidation of the silicon nitride substrate for HfSiO4 coated sample was smaller
than that of other two. Many cracks were in ASiO4 EBC layer during the corrosion test. The
introduced crack length in HfSiO4 EBC layer is shorter than in ZrSiO4 EBC layer due to the thermal
expansion mismatch between EBC materials and the silicon nitride substrate.
Accelerated Degradation Test of Indium Tin Oxide (ITO) Thin Films Deposited by RF Magnetron Sputter
Authors: Shin Hyun Gyu , Kim Yong Nam , Song Jun Kwang , Lee Hee Soo
Published: March 2009

Thermal degradation of indium tin oxide (ITO) thin film has been investigated. ITO thin
film was fabricated on glass substrate using RF magnetron sputtering and was characterized. The
resistivity of the film which was thermally degraded at high temperatures in air atmosphere was
increased highly. Thermally-degraded specimen was analyzed using XPS and Hall measurement to
reveal failure mechanism. Result showed that failure mechanism was the decrease in charge carrier
concentration and mobility due to oxygen diffusion and chemisorption. Accelerated degradation test
(ADT) was performed to predict the lifetime of ITO thin film. The lifetime under normal operating
condition could be predicted via statistical analysis and modeling of data acquired from ADT of a
short period.
Electrical Properties of AlN-SiC Ceramics
Authors: Kobayashi Ryota , Tatami Junichi , Wakihara Toru , Meguro Takeshi , Komeya Katsutoshi
Published: March 2009

AlN-SiC ceramics with 0 to 75 mol% of AlN were fabricated through pressureless sintering of very fine AlN and SiC. Powder compacts with different amounts of AlN were fired at 2000°C for 1 h in Argon gas flow using an induction-heating furnace. The microstructure and phases present in the products were evaluated using SEM and XRD. The AlN-SiC ceramics had a porous structure with 30% porosity, and the grain size was increased with the addition of AlN. XRD analysis showed that 2H was a main phase in all samples, though 3C and 6H phases were found in 25 mol%AlN-75 mol%SiC ceramic. The electrical properties of the AlN-SiC ceramics were evaluated at various temperatures ranging from room temperature to 300°C. The electrical conductivity of the AlN-SiC ceramics depended on the amount of AlN and on the temperature. The 75 mol%AlN-SiC ceramic had higher electrical resistance, though the other samples were electrical conductors. The highest electrical conductivity was obtained with the 25 mol% AlN composition, which was 7 S/m at room temperature and 30 S/m at 300°C. The Seebeck coefficient for the AlN-SiC ceramics increased with rising temperatures. The AlN-SiC ceramics with 50 mol%AlN had the highest Seebeck coefficient of 220 2V/K at 300°C.
Effect of Magnesium Ion on the Precipitation of Hollow Calcium Carbonate by Bubble Templating Method
Authors: Hadiko Gunawan , Han Yong Sheng , Fuji Masayoshi , Takahashi Minoru
Published: March 2009

Hollow calcium carbonate (CaCO3) particles were synthesized by bubbling CO2 in the solution of calcium chloride (CaCl2) with the presence of ammonia at room temperature. In this method, CO2 bubble, besides as reactant, has an important role as a template for forming hollow particles. The precipitation was carried out by controlling the precipitation condition, such as pH, flow rate and additives. Hollow calcium carbonate particles were precipitated with the major crystal phase of vaterite. An interesting finding is that magnesium ion (Mg2+) can suppress the transformation of vaterite to calcite by inhibiting the growth of the calcite.
Preparation and Electrical Properties of Carbon Nanotubes Dispersed Zirconia Nanocomposites
Authors: Ukai T. , Sekino Tohru , Hirvonen Ari T. , Tanaka Norihito , Kusunose Takafumi , Nakayama Tadachika , Niihara Koichi
Published: March 2009

Multi Wall Carbon Nanotubes (MWCNTs) with a diameter of 20-30 nm were used as a
conductive phase to add electric conductivity to yttria stabilized tetragonal zirconia (3Y-TZP).
Almost fully dense 3Y-TZP/MWCNTs nanocomposite was obtained by pressureless sintering under
inert atmosphere and Hot Isostatic Pressing (HIP) treatment. The conductivity of the
nanocomposites increased with increasing content of MWCNTs. Moreover, the fracture toughness
increment of the composite was confirmed at 0.5 wt% addition. Scanning electron microscopy and
transmission electron microscopy observation of the microstructures showed that MWCNTs were
fairly homogeneously dispersed in the 3Y-TZP matrix.
Honeycomb Supports, Filters and Catalysts for Cleaner Environment
Authors: Shukla S.P. , Madhusoodana C.D. , Das Rathindra Nath
Published: March 2009

The extruded honeycomb supports, porous filters and catalyst monoliths are innovative ceramic products used in environmental protection. The development and applications of these novel materials and products are mainly driven by the environmental legislation in the region, the availability of technology, the mass manufacturing facilities and the cost effectiveness. This paper highlights some of the recent innovations and challenges in ceramic materials and design, and our findings in systematic understanding and applications of the principle of fabrication of honeycomb ceramics for various air pollution control systems in India. The use of locally available platy kaolin and advanced extrusion process control using rheological parameters of the paste are advantageously adopted for production of thin walled and high thermal shock resistant cordierite honeycomb supports for catalytic converters. The low cost design of diesel particulate filter (DPF) with off board electric regeneration system is found to be very effective in reducing the particulate emission in urban transport buses and proven for more than 100,000 km on Indian roads. The Ti-WV based SCR catalyst extruded in the form of honeycomb using high surface area TiO2 has shown high NOX reduction in coal fired boiler exhaust. The preparation of high surface area honeycombs from activated carbon and zeolites with adequate mechanical strength opens up new application areas. Some of the case studies on the above products and applications are presented in this paper.
The Preparation of Visible Light-Responsive TiO2 Thin Films by Applying a RF-Magnetron Sputtering Deposition Method and Their Photocatalytic Reactivity for the Decomposition of Water with a Separate Evolution of H2 and O2
Authors: Kitano Masaaki , Kikuchi Hisashi , Hosoda Takahiro , Takeuchi Masato , Matsuoka Masaya , Eura Takashi , Anpo Masakazu , Thomas John M.
Published: March 2009

TiO2 (Vis-TiO2) thin films absorbing UV and visible light in regions of 250-600nm have
been successfully developed by applying a radio-frequency (RF) magnetron sputtering deposition
method. SIMS depth profiles of Vis-TiO2 revealed that the O/Ti ratio gradually decreases from the
top surface (O/Ti ratio : 2.00 ± 0.01) to the inside (1.93 ± 0.01). This unique declined O/Ti
composition (anisotropic structure) may be the origin of the significant perturbation in the electronic
structure of Vis-TiO2, enabling the absorption of visible light and their high photocatalytic
performance under visible light irradiation. In fact, it was found that the separate evolution of H2 and
O2 from water could be successfully achieved under visible light or solar light irradiation by applying
these thin film photocatalysts in an H-type glass container separating the two aqueous solutions by a
TiO2 thin film and proton-exchange membrane, having H2 evolution from Pt side and O2 evolution
from TiO2 thin film side, respectively.
Magnetic and Electronic Properties of Transition Metal Doped β-SiC - A Diluted Magnetic Semiconductor
Authors: Kim Yoon Suk , Kim Han Chul , Chung Yong Chae
Published: March 2009

We used ab initio pseudopotential plane wave methods to study the magnetic and electronic
properties of transition-metal doped ¯-SiC. It is found that the SiC:Cr reveals stable ferromagnetism
with permanent magnetic moments as large as 2 μB regardless of substitution site. In addition, the
SiC:CrSi is predicted to have good electron mobility and wide spin band-gap of 1.58 eV with the
Fermi level at the center of the gap, which is desirable for realizing spintronic devices.
Effect of Additives on Hydrolysis of Ti Alkoxide and Microstructural Observation of TiO2
Authors: Nakahira Atsushi , Fujita Y. , Kubo T. , Eguchi S. , Nishida S. , Isshiki Toshiyuki
Published: March 2009

By the usage of the hydrolysis of Ti alkoxide, various types of TiO2 were obtained through
the addition of catalyst (HCl, NH4OH, and CH3COONH4) and some additives into Ti alkoxide
solution at room temperature. In special, the effect of two additives, diethylene glycol (DEG) and
hexamethylphospheric triamide (HMPA), on hydrolysis behaviors and microstructure with various
catalyst for hydrolysis of Ti-tetraisopropoxide was in detail investigated. In case of TiO2 powder with
HMPA as an additive, the crystallinity of TiO2 except with NH4OH as a catalyst decreased in XRD
patterns, compared to those of products with no additive and with DEG as an additive. The addition
of HMPA prohibited the growth of TiO2 and led to fine TiO2 with the average particle size of
approximately 10nm.
Fabrication and Fuel Cell Properties of Gd-Doped CeO2 Micro-Tube Ceramics Reactors Prepared by Gel Precursor
Authors: Fujishiro Yoshinobu , Hamamoto Kouich , Mangalaraja Ramalinga V. , Awano Masanobu
Published: March 2009

Micro-tube type Gd-doped CeO2(CGO) reactor were prepared by hydrolysis of metal acetate
gel at room temperature. The size of anode tube was ca. 0.8mm in diameter, and length was
20mm after sintering at 1400°C. DC conductivity of the prepared dense CGO cell consisting
of 500nm grains was about 10 Ohm-cm at 600°C. Electrical power density of the micro-tube
fuel cell, which was coated both CGO electrolyte and CGO/La0.6Sr0.4Co0.2Fe0.8O3 cathode on
the surface of 40vol%NiO-CGO anode tube, was about 900mW/cm2 at 600°C under
30ml/min H2 gas flowing.
Internal Friction and Mechanical Strength of Hydrogenated Ti-Rich Multicomponent Glassy Alloys
Authors: Hasegawa Masuyuki , Takeuchi M. , Nagata D. , Wada T. , Kato Hidemi , Yamaura Y. , Inoue Akihisa
Published: March 2009

The hydrogen-induced internal friction and mechanical strength of the Ti-rich
Ti34Zr11Cu47Ni8 and (Ti34Zr11Cu47Ni8)98Si2 hydrogenated glassy alloys have been investigated. It is
found that the tensile strength is more than 0.8 GPa at room temperature when the hydrogen content is
below about 20 at% for both alloys. The frequency dependence of peak temperature of the
hydrogen-induced internal friction of (Ti34Zr11Cu47Ni8)98Si2-17.3 at%H hydrogenated glassy alloys
has been clarified. Activation energy and pre-exponential factor are estimated to be 0.35 eV and
1.3x10-12, respectively. Compared with these values with those of Zr40Cu49Al10Si1 hydrogenated
glassy alloys which show an internal friction peak around 300 K at about 300 Hz, it is found that the
activation energy is much smaller than that of the latter although the pre-exponential factor is almost
the same. Considering their similar composition and different component (Al), it is suggested that the
component Al of the latter glassy alloys is effective for the higher activation energy which results in
the increase of the peak temperature.
Can Metallic Glass Damping Be Increased by Stress Training Treatment?
Authors: Aboki Tiburce A. M.
Published: March 2009

We have subjected Zr59Cu20Al10Ni8Ti3 glassy sample to internal friction thermal cycle (IFTC) measurements under various conditions involving changes in heating/cooling rate, strain amplitude and frequency. Additional low temperature internal friction peaks (ALTIFP) were found to occur with the characteristic low temperature internal friction peak (CLTIFP) observed for some glassy alloys. The ALTIFP were enhanced on heating and reduced on cooling. Their strength increase following the number of IFTC can be related to a stress concentration in some zones of the glassy structure, which is abruptly relaxed by the viscous flow creating interfaces in the glassy structure. These interfaces are likely to be formed between atomic clusters. The growth of the ALTIFP increases significantly the whole IF level (IFL) from 10-4 to 10-2 enhancing the damping capacity of the glassy sample.
Applications of High Damping Stainless Alloy (HIDAS)
Authors: Igata N.
Published: March 2009

Fe-12Cr-22Mn and Fe-12Cr-22Mn-2Co (High Damping Stainless Alloy HIDAS) were
developed and applied for suppression of noise or vibration. Since these alloys have high strength
(1400Mpa) as well as high damping capacity (1020) due to/ interface, their direct
replacements for the parts of machines were possible. In this respect, the applications were tried
mainly to machineries and nanotechnologies. Those were bolt and nut, gear, bite shank, cutting
tool of numerically controlled (NC) machine, brake and arm of hard disk drive (HDD) and others.
In those applications, all data obtained showed better results compared with other materials. Cost
down and quality control would be the remaining problems.
Damping Mechanisms in High Damping Materials
Authors: Golovin Igor S.
Published: March 2009

Different viewpoints at high damping materials - from engineering needs to physical mechanisms are discussed. It is suggested that only several mechanisms in metallic materials can lead to high intrinsic damping capacity while some other “peak-like” effects are not sufficient to make high damping materials.
Effect of Heat Treatments on the Damping Characteristics of TiNi-Based Shape Memory Alloys
Authors: Yoshida I. , Otsuka Kazuhiro
Published: March 2009

Low frequency internal friction of Ti49Ni51 binary and Ti50Ni40Cu10 ternary shape memory alloys
has been measured. The effect of solution and aging heat treatments on the damping property was
examined. The temperature spectrum of internal friction for TiNi binary alloy consists, in general, of two
peaks; one is a transition peak which is associated with the parent-martensite transformation and is rather
unstable in a sense that it strongly depends on the frequency and decreases considerably when held at a
constant temperature. The other one is a very high peak of the order of 10-2, which appears at around 200K.
It appears both on cooling and on heating with no temperature hysteresis, and is very stable. The behavior
of the peak is strongly influenced by the heat treatments. The trial of two-stage aging with a purpose of
improving the damping capacity has been proved unsatisfactory. TiNiCu has a very high damping, the
highest internal friction reaching 0.2, but by quenching from very high temperature, say 1373K, the
damping is remarkably lowered. For the realization of high damping the quenching from a certain
temperature range around 1173K seems the most preferable condition.
Susceptibility of Damping Behavior to the Solidification Condition in the As-Cast M2052 High-Damping Alloy
Authors: Yin Fu Xing , Iwasaki Satoshi , Sakaguchi Takuya , Nagai Kotobu
Published: March 2009

M2052 alloy is a MnCu based high damping alloy that shows high damping capacity and
the superior workability. In the present work, the microstructure and damping behavior of the alloy in
different solidification cooling rates are investigated with directionally cast alloy plate. For the
variation of solidification cooling rate in the range of 250~10K/s, the secondary dendrite arm spacing
of the cast alloy changes from 4 to 18mm and grain size varies in the range of 100~200mm except the
surface regions and center regions in the cast plate. As compared to the worked and heat treated alloy,
the as-cast alloy shows a high temperature damping above the average phase transformation
temperature of the alloy irrespective to the solidification cooling rate. On the other hand, a higher
damping peak is observed in the cast alloy which is attributed much to the twin boundary damping,
however, the magnitudes of the damping peak are found to be varied corresponding to the respective
solidification conditions.
Evaluation of Planar-Type Thin Film ZnO Varistors Fabricated Using Pulsed Laser Ablation
Authors: Sawa Sayuki , Yoshikado Shinzo
Published: March 2009

Planar-type thin film Bi-Mn-Co-doped ZnO varistors were fabricated on a silica glass substrate or a
sintered alumina substrate using a visible light (532 nm) pulsed laser ablation method. The deposited
thin films were annealed at 800°C or 900°C in air. For the thin films deposited on alumina substrates
and then annealed, the contents of Bi and Mn decreased compared with those of the as-deposited films.
Voltage-current (V-I) characteristics of the thin-film varistor fabricated on the alumina substrates and
annealed showed nonlinearity. The nonlinearity index α was approximately 10 for the thin film
deposited on the alumina substrate and annealed at 800°C in air using a target of ZnO doped with 2.5
mol% Bi2O3, 0.5 mol% MnO2 and 0.2 mol% Co3O4. Moreover, the current density of 20 A/cm3 was
relatively high for safety use.
Preparation of Three Dimensionally Ordered Macroporous Li4Ti5O12 Electrode
Authors: Woo Sang Wook , Dokko Kaoru , Kanamura Kiyoshi
Published: March 2009

Three dimensionally ordered macroporous (3DOM) Li4Ti5O12 was successfully prepared by a
colloidal crystal templating process. Colloidal crystal consisting of monodisperse polystyrene
particles (1 9m diameter) was used as a template for the synthesis of macroporous Li4Ti5O12. A
precursor sol consisting of titanium isopropoxide and lithium acetate was injected into the template,
and it was calcined at high temperatures. A macroporous membrane of Li4Ti5O12 with
inverse-opal structure was obtained. The prepared material had a spinel-related crystallographic
structure. The interconnected pores with uniform size (0.8 9m) were clearly observed on entire
part of the membrane. The electrochemical properties of the 3DOM Li4Ti5O12were characterized
with cyclic voltammetry and glavanostatic charge-discharge in an organic electrolyte containing a
lithium salt. 3DOM Li4Ti5O12 exhibited a discharge capacity of 160 mA h g-1 at the electrode
potential of 1.55 V vs. Li/Li+ due to the solid state redox of Ti3+/4+ accompanying with Li+ ion
insertion and extraction. The discharge capacity was close to the theoretical capacity (167 mA h
g-1). This means that the Li+ insertion and extraction took place at all part of the 3DOM Li4Ti5O12
membrane.
Computational Simulations of Li Ion Conduction in (Li,La)TiO3
Authors: Okumura Toyoki , Dodomi Ayumi , Saito Morihiro , Kuwano Jun
Published: March 2009

The locations and local environments of the Li ions in La0.56Li0.33TiO3 have been investigated by
classical molecular dynamics (MD) simulations and first-principles (FP) calculations. The pair
correlation functions of Li-O and Li-Ti indicate that the Li ions are located somewhat broadly
mainly in the vicinity of the midpoint between the center of the A-site and the center of the
bottleneck formed by four O2-. This is consistent well with that suggested from previous neutron
diffraction and 6Li-NMR studies. The FP calculations suggest a different location of the Li ion in
the vicinity of the midpoint between the centers of two adjcent bottlenecks; however it coincides
with one of the locations shown by the trajectories simulated with the MD calculations.
Absolute Single-Mode Lamb Wave Generation by Laser in a Thin Plate
Authors: Lee Seung Seok , Dho Sang Whoe
Published: March 2009

We present a laser-ultrasonic technique to generate the lowest symmetric ( ) Lamb
wave in a thin plate. Using this special technique, in which two symmetric laser beams
quasi-simultaneously hit at the same point on both sides of the plate, we absolutely suppress
anti-symmetric Lamb wave modes. This technique is applicable to any situation that requires
symmetric Lamb wave mode operation and does not need additional contacts or special equipments.
Characterization of the Harmonic Generation from Cavitating Bubbles Interacted with a Diagnostic Ultrasound in the Focal Region of High Intensity Focused Ultrasound
Authors: Choi Min Joo , Kang Gwan Suk , Paeng Dong Guk , Rhim Sung Min , Bae Moo Ho , Zeqiri Bajarm , Coleman Andrew
Published: March 2009

Harmonic image (HI) has been proposed to be promising for visualizing lesions produced
by therapeutic high intensity focused ultrasound (HIFU). The study characterizes harmonics
generated from the bubble cavitating at the focal region of a therapeutic HIFU field in response to a
typical diagnostic ultrasound. Based on Gilmore model, it was simulated the nonlinear dynamics of
the bubble being resonated at 1 MHz of the therapeutic ultrasound and driven by a typical 3.5 MHz
diagnostic pulse. It was shown that harmonic generation increased with MI in a sigmoid pattern
where the rapid and transient changes occurred between 0.5 and 2 in MI. For whole ranges of MI
(less than 8), the sub-harmonic was the predominant in magnitudes over other harmonic bands. This
reveals that, if HI is considered for improving the detection of focal legion highly cavitating caused
by a HIFU field, the sub-harmonic component would be a preferred parameter rather than the 2nd
harmonic which has been commonly used in current harmonic imaging.
Residual Stress Evaluation of Thin Film Using Strip Bending Test
Authors: Kim Jae Hyun , Lee Hak Joo , Han Seung Woo , Kim Jong Man , Baek Chang Wook
Published: March 2009

In this study, we use the strip-bending test to measure the residual stress of a thin film
structure. The principle of the strip bending test and the test procedures are described and the analysis
of the strip deformation is presented. The explicit formula for estimating the residual stress is given,
which requires the initial stress as an input. As an example, the E-beam evaporated Au thin film is
chosen, and the residual stress is measured by the present method. The Au thin film structure has a
tensile or compressive residual stress depending on the film thickness. The tensile and the
compressive residual stresses of Au thin film are successfully measured by the present method.
Automated Multichannel Signal Classification Systems for Ultrasonic Nondestrucitve Evaluation
Authors: Kim J. , Ramuhalli P. , Udpa L. , Udpa S.
Published: March 2009

A key requirement in most ultrasonic weld inspection systems is the ability for rapid
automated analysis to identify the type of flaw. Incorporation of spatial correlation information from
adjacent A-scans can improve performance of the analysis system. This paper describes two neural
network based classification techniques that use correlation of adjacent A-scans. The first method
relies on differences in individual A-scans to classify signals using a trained neural network, with a
post-processing mechanism to incorporate spatial correlation information. The second technique
transforms a group of spatially localized signals using a 2-dimensional transform, and principal
component analysis is applied to the transform coefficients to generate a reduced dimensional feature
vectors for classification. Results of applying the proposed techniques to data obtained from weld
inspection are presented, and the performances of the two approaches are compared.
Development of a Manipulator Free Mobile Ultrasonic C-Scan System
Authors: Cho Hyun , Song Sung Jin , Kim Hak Joon , Lee Hee Jong , Choi Sung Nam
Published: March 2009

Ultrasonic C-scan inspections have been used in various industrial fields. Usually,
conventional ultrasonic C-scan systems have several mechanical manipulating axis controlled by a
computer or an electronic device. These systems are suitable for the high resolution and inspection
quality. But they are too heavy and bulky to carry in general, and many industrial fields do not require
higher resolution than a hundred micron order. To take care of such a need, in this study we developed
an ultrasonic C-scan system that does not have any mechanical manipulator to transport ultrasonic
transducers. This system, named "M-Scanner", adopts an electro-magnetic position tracking sensor
instead of mechanical manipulating axes in order to trace the transducer position. Furthermore, this
new system is portable and has a reasonable construction cost along with practical inspection
resolution required in many industrial field inspections.
Novel Test Procedure of Tensile Test for MEMS Materials
Authors: Park Jun Hyub , Kim Yun Jae , Myung Man Sik , Lee Chang Seung , Choa Sung Hoon , Choi Nam Sup
Published: March 2009

This paper describes a novel test procedure, new structure of specimen easy to manipulate, align and grip a thin-film and test machine for a tensile and fatigue test. For the proposed specimen, the surroundings of the specimen including the side support strips except for six bridges are etched during the fabrication of the specimen, which in turn makes it possible to cut off easily the specimen from the wafer by minimizing a damage to the test film and also possible to produce the specimen in mass production. For the present specimen, a small hole is made at the grip end and using a small pin for setting the specimen onto the tester, the setting process and alignment of specimen is much easier, compared to the specimen proposed by Sharpe et al. To gain confidence in reliability of testing results, pre-test using the Al-3%Ti is performed, which is widely used in the RF switch and other MEMS devices. Tensile tests are performed, from which tensile strengths of the Al-3%Ti are measured as 343±16.22MPa at 200μm width and 1.1μm thickness.
Influence of Anisotropic Materials on Stress Intensity Factor under Biaxial Stress Conditions
Authors: Shimomura Taku , Shimamoto Akira
Published: March 2009

Polymer materials are used in the structural members such as aircraft, ship, automobiles in order to enlarge and lighten the machinery and structures. In such the machinery and structures, the complex destruction phenomena are generating by the deterioration of use conditions of the polymer materials. And the materials are placed under biaxial or multi-axial stress conditions rather than uni-axial stress conditions due to their complicated structures. To understand the basic deformation behaviours and the features in destruction process under multi-axial stress conditions is more important in the reliability and the accident prevention plan. To help overcome this problem, the authors have developed a hydraulic high-speed biaxial loading test device. In this study, we had comparative study for the values of the dimensionless stress intensity factors, F values by the photoelastic and caustics methods to clarify deformation behaviours and characteristics of polymer materials under biaxial stress conditions.
Nondestructive Structural Analysis on 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 melt foaming technology was investigated under deformation with fine-focus X-ray 3D-CT to make clear the development target porous material for automobile industries with improved reliability. It was confirmed that structures with more fine, more uniform and exclusion peculiar anisotropic pores would make improved mechanical properties of the material.
Strength-Based and Wave-Based Liquefaction Characterization
Authors: Cho Gye Chun , Lee Jong Sub
Published: March 2009

The purposes of this study are to analyze post liquefaction shear strength and to explore the
potential use of wave-based techniques to monitor liquefaction and post liquefaction response. The
first part presents a detailed analysis of triaxial test results to identify robust strength criteria. The
second part documents experimental data on the characterization of liquefaction events with P-wave
reflection imaging and S-wave trans-illumination techniques. The relevance of multiple coexisting
temporal and spatial scales is highlighted. The following results are obtained: 1) the post liquefaction
shear strength can be estimated within the framework of critical state soil mechanic; 2) the P-wave
reflection images obtained before and after liquefaction represent the depression of the soil-water
interface; 3) excess pore pressure migration from liquefied deep layers may cause zero-effective stress
in dilative shallow layers. P-wave reflection is a valuable tool to monitor the evolution of subsurface
structures and S-wave trans-illumination technique can be used to yield a comprehensive picture of
the spatial evolution of liquefaction.