bluuebunny/crossref_metadata_2025 huggingface dataset:
The Application of Cryogenic Pneumatic Mist Jet Impinging in High-Speed Milling of Ti-6Al-4V
Authors: An Qing Long , Fu Yu Can , Xu Jiu Hua
Published: March 2009

To solve the problems caused by high temperature in the cutting zone during high-speed
milling of Titanium alloys, some cooling methods are employed, such as cold air cooling, high
pressure coolant jet impinging, MQL, etc. But all have their shortfalls, both in cooling efficiency
and environmental pollution. Here a new high efficiency cooling technology-cryogenic pneumatic
mist jet impinging (CPMJI) cooling technology is offered. In this technology, a little quantity of
coolant is carried by high pressure cryogenic air (-20) and reaches the machining zone in the
form of mist jet. This paper mainly focuses on the cooling effects of CPMJI in high-speed milling
of Titanium alloy Ti-6Al-4V, as compared with dry, cold air cooling and MQL conditions. CPMJI
greatly reduced the temperature in cutting zone and flank wear of tool.
Research on High Speed Ball-End Milling Forces
Authors: Jiang Bin , Zheng Min Li , Yang Shu Cai , Fu M.
Published: March 2009

Based on the experiment of high speed milling ball-end milling forces, the model of
ball-end milling force is established for high speed machining complex surface by differential
method, and research on the principle of high speed ball-end milling force. Results show that the
parameters of cutting layer are subjected to varying curvature of complex surface, and place in the
unstable state, cutting force decreases as the curvature and the inclination angle increase. By means
of lessening cutting speed’s grads and adjusting the inclination angle and the path interval of cutter
to the variety of curvature, cutting force and its fluctuation can be depressed availably; the process
of high speed ball-end milling can be obviously improved.
The Effects of Rare Earth on the Hot Pressing of Cu-Sn-TiH2 Bonded Diamond Composites
Authors: Yu Yi Qing , Tie Xiao Rui , Li Yuan , Xu Xi Peng
Published: March 2009

The present study was undertaken to examine the effects of rare earth (RE) in hot pressing
of Cu-Sn-TiH2-bonded diamond composites. Two kinds of composite specimens – with RE and
without RE – were fabricated. As an additive to the Cu-Sn-TiH2 bond matrix, the RE was used in the
form of misch-metal. The hardness and transverse rupture strength (TRS) of the specimens were
measured. SEM and EDS were used to analyze the fracture surfaces of the specimens. Both hardness
and TRS of the specimens with RE were found to be higher than the specimens without RE. SEM
observations indicated that the pop-outs of diamonds on the fracture surface of the segments without
RE are more than the specimens with RE. But more diamonds were fractured on the fracture surface
of the segments with RE.
Analyses on the Solution Areas of Multi-Point Machining Constraints
Authors: Wang Rui Qiu , Chen Wu Yi , Jin M. , Pang J.Y. , Ye H.T.
Published: March 2009

Hermite method and MPM method were studied. Multi-point machining constraints with
the cutter tilting forward and backward were derived respectively. So the number of the solutions of
the two Multi-point machining methods was doubled than before. To derive some general
conclusions about solution areas of Multi-point machining constraints, structure of neighborhood
region close to a given point on a surface was used to substitute the surface in the Multi-point
machining error calculation. A computational example was also given in the paper. With the
theoretical analyses and computational example, it was proved that, for an open and slightly curved
surface machining with Multi-points method, without regard to interference, there were four branch
areas satisfying Multi-point machining constraints and distributing radically nearby the first tangent
contact points respectively on condition that the cutter was tilted forward or backward. And they
extended basically in the directions along the principal curvatures at the first tangent contact point.
Arc Envelope Truing of Metal-Bonded Diamond Grinding Wheel by Use of Cone-Shaped Truer
Authors: Xie Jin , Tamaki Junichi , Tang Yong
Published: March 2009

This paper introduces a new arc envelop truing method of metal-bonded diamond grinding.
It utilizes the arc profile of rotary cone-shaped truer, namely electrode, to envelop wheel profile
during Electro-Contact Discharge (ECD) truing. The aim is to realize precision truing of diamond
grinding wheel profile for grinding of hard-brittle material. The arc envelope truing principle of wheel
profile was analyzed by the use of 3D spatial geometry to identify lean angle of the truer. Then the arc
envelop truing and grinding experiments were carried out to investigate truing precision and ground
surface in comparison with straight truing and GC stick truing. It was confirmed that the arc envelope
truing can obtain sub-micro truing precision of metal-bonded diamond grinding wheel at the depth of
cut of micro degree. It may improve greatly form accuracy and ground surface.
Machinability for Turning of 1Cr18Ni9Ti Austenitic Stainless Steel with Ceramic Tool
Authors: Liu Zhan Qiang , Wang J.M. , Wan Yi
Published: March 2009

High strength, low thermal conductivity, high ductility and high work hardening tendency of stainless steels are the main factors that make their machinability difficult. In this study experiments for high-speed turning of 1Cr18Ni9Ti stainless steel were carried out with ceramic tools. The influence of cutting speed on tool wear, chip formation as well as chip color, and surface roughness were investigated. A decrease in tool nose wear was observed with increasing the cutting speed up to 210 m/min. Surface roughness (Ra) was also decreased with increasing the cutting speed. Correlation was made between the tool nose wear/surface roughness and the chips obtained at the three cutting speeds of 110, 160 and 210 m/min.
The Abrasion Mechanism of Diamond Coated Blades with Ultraviolet-Cured Resins
Authors: Yao C.Y. , Peng Wei , Gao Tao
Published: March 2009

In recent work, a creative idea has been proposed by applying the rapid prototyping
technology to develop a new diamond-coated blade based on ultraviolet-cured resin bond. The new
technology features many advantages such as fast processing speed, low environmental pollution,
and low energy consuming. This paper makes an investigation on the adherence and abrasion
mechanisms of such diamond blades. The experimental plan is well designed for selection of an
optimal prescription of the mixture to achieve good mechanical performance and a manufacturing
process is proposed to produce ultraviolet-cured resin bonded diamond coated blades. Practical
experiments are carried to test the blade performance and to compare with different tools in incising
artificial crystal. Furthermore, this paper also observes how the tensile strength and elastic modulus
of ultraviolet-cured resin affect the crevasse and quality of machined edge surfaces.
Microstructure and Property of Nickel Electroformed Using Rotating Cathode in Hard Particles
Authors: Zhu Z.W. , Zhu Di
Published: March 2009

Nickel deposits were electroformed by a novel technique, in which the mandrel rotated in
hard particles (such as ceramic beads) filling between the electrodes. The microstructure and
microhardness of the deposit were studied by means of SEM, XRD analysis in contrast with the
traditional method. The effects of current densities on the surface morphology and microhardness of
the deposit were also studied. The results showed that the polishing, impacting and disturbing of
hard particles during electrodepositing could affect the microstructure and performance of the
deposits. The grains were substantially refined, the preferred orientation of (200) face weakened
and the microhardness significantly increased. Moreover, the presented technique could use higher
current density and produce bright and smooth deposits.
Grains Ultra-Refinement of Materials Imposed by Pulse Laser
Authors: Zhou Ming , Zhu X.Q. , Dai Q.X. , Cai Lan
Published: March 2009

Submicron-sized top layer was synthesized on an austenitic stainless steel sample by adopting laser shock processing (LSP). The substructures were characterized and examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), moreover, the mechanism of ultra-refinement laser-induced was analyzed. It showed that a refined top surface with average subgrains size of 0.5(m was synthesized by the model of single laser loading, black paint as absorption coating and the peak pressure induced by LSP approximating twice of the dynamic yield strength of target. It indicated that thermoplastic destabilization had happened in heavily localized regions imposed by LSP. Streak-like subgrains were oriented perpendicular to shock wave (Gaussian profile) vector. In order to accommodate plastic strain, streak-like subgrains experienced necking, breaking up and dynamic rotational recrystallization, as a result, the submicron grains were formed on the surface of sample.
A Study of Precision Sub-Dry Cutting Mechanism
Authors: Ren J.L. , Lu S. , Ren J.J. , Gong S.D.
Published: March 2009

This paper analyzes the changes of cutting force, cutting temperature, and cutting-tool wear
in the process of precision cutting. All these factors are considered in the test on GCr12, Cr12 and 45
steels. This test uses the sub-dry cutting method with green-air cooling and a little additive.
Furthermore, it discusses the feasibility of sub-dry cutting on the basis of a comparison with other
cutting methods
A Research of Image-Based Visual Control in Microassembly under a Microscope
Authors: Tian Shi Jie , Li B. , Jiang Zhuang De , Guo Jun Jie , Zhao H.Y.
Published: March 2009

A new visual servo control system under microscope was introduced based on the
research of image-based computer visual control system, including the installation and calibration of
camera, deduction of the image Jacobian and the algorithm of controlling and so on. The
experiments of motion controlling and positioning showed that one pixel about 2.97μm can be
reached easily in single axes under 5× eyepiece and under the same condition a 400μm micro shaft
was assembled into a micro-gear with 415μm inner bore. Knowing from the control algorithm, the
accuracy of the system is independent on errors in the robot kinematics or the camera calibration.
The research results indicate that this method is a full closed-loop visual servo control system with a
high reliability and simple control algorithm and it can be used in microassembly system.
Study on the Compound Fuzzy Motion Control for the Ultra Precision Machine Tools
Authors: Wang Bo , Liang Ying Chun , Dong Shen
Published: March 2009

This paper presents a sophisticated trajectory tracking algorithm based on the utilization of the compound control and fuzzy contour control for the ultra precision machine tools. The main idea is to use the compound control to broaden the bandwidth of the servo system and, therefore, improve the tracking accuracy of the single axis. Then, FUZZY cross coupled contour control is introduced to compensate for the contour error caused by imperfect dynamics of the tracking axis and the mismatch of the control parameters of the servo systems. Experiments carried out on the HCM-1 ultra precision machine tool with a T-type layout show that the integration of the compound control with the fuzzy cross coupled contour control can effectively improve the contour tracking accuracy of the ultra precision machine tool.
Kinematics and Simulation for a High-Precision Parallel Kinematic Platform
Authors: Hu Ying , Hu Hong , Li B.
Published: March 2009

To meet the high speed and high precision requirements of machining freeform workpieces, a 4-DOF parallel kinematic platform with the configuration of 4 actuated legs plus a passive leg is proposed in this paper. Inverse kinematics and the calibration algorithm are developed, and virtual prototype modeling and kinematic simulation using MSC/ADAMS are carried out. The simulation results exhibit that the proposed structure is capable of implementing the high-precision machining requirements of freeform parts.
Analysis of the Static Performance of Externally Pressurized Gas Journal-Thrust Bearing with Slot Restrictors
Authors: Du Jian Jun , Yao Ying Xue , Liu D. , Feng D.W.
Published: March 2009

The externally pressurized gas journal-thrust bearing with slot restrictors is investigated by the finite element technique. A consistent transform principle is proposed in this paper to simplify the analysis of Reynolds equation for journal and thrust bearing. The second-order partial differential equation, Reynolds equation, is reduced by one-order with weighted residual method in the discretization procedure, which releases the requirement of continuity degree of the interpolation function while finite element method is adopted. The static characteristics of externally journal-thrust gas bearing are analyzed. Factors that influence the radial and axial bearing capacity are discussed. The interactional rules that exist between the journal bearing part and thrust bearing part are discovered. Predicted characteristics are in good agreement with experimental results.
Preparation and Properties of Silicon Nitride Ceramics by Nitrided Pressureless Sintering (NPS) Process
Authors: Han In Sub , Cheon Seung Ho , Chung Yong Hee , Seo Doo Won , Lee Shi Woo , Woo Sang Kuk , Lee Kee Sung
Published: March 2009

Silicon nitride ceramics were prepared by new nitrided pressureless sintering (NPS)
process in this study. The microstructures, strengths and thermal properties of the NPS silicon nitride
ceramics containing three types of Al2O3 and Y2O3 sintering additives were investigated. Additionally,
we have investigated the effect of silicon metal contents changing with 0, 5, 10, 15 and 20 wt% in
each composition. The silicon nitride was successfully densified using NPS process, particularly at
the starting composition of 5 wt.% Al2O3, 5 wt.% Y2O3, and 5 wt.% Si addition. The maximum
flexural strengths and relative densities of these specimens were 500 MPa and 98%, respectively. The
flexural strength of sintered specimens after the thermal shock test between 30oC and 1300oC for
20,000 cycles was maintained with the original laboratory strength of 500MPa by low thermal
expansion coefficient, 2.9 × 10-6/oC, and high thermal conductivity, 28 W/m⋅oC.
Dispersion of Barium Ferrite Particles for Slip Casting in Magnetic Field
Authors: Li Jing Long , Sano Saburo , Tsuzuki Akihiro , Gotou Akihiro , Shibasaki Yasuo , Zhang Fu Sheng , Xiong Jiang Tao , Zhang Yong , Ma Tie Jun
Published: March 2009

Water-based slurries containing barium ferrite particles have been prepared and slip cast
in magnetic field. This paper presents the characteristics of the suspensions in terms of Iso-Electric
Points (IEP) and zeta potential that were evaluated through pH titration and polymer adsorption.
Both enlarging the specific surface area of particles by planetary milling and adjusting the pH to
low value apparently increase the zeta potentials. Stable slurry was obtained by adding polyethylene
glycol (PEG) into the suspension at pH = 2 ~ 3.5. The steric repulsion plays key role in dispersion
and PEG films served as insulative layers and mechanically kept particles from contact each other.
The barium ferrite particles formed many stacks of plates during slip casting, which either aligned
randomly without magnetic field applied or regularly aligned to form textured structure when
magnetic field was applied.
The Vibrative Casting with a Thixotropic Behavior
Authors: Yoon Seog Young , Lee Jong Kook , Hwang Kyu Hong , Jun B.S.
Published: March 2009

To prepare the vibrated casting slurries of waste tile particles, ultrafine colloids of the waste
tile was added as a binder materials and as a thixotropic agent to avoid segregation between large and
fine grains. The plasticity of the slurries was controlled by the rheology of colloids of the waste tile. To
give thixotropic behavior, the dispersion and coagulation behavior of the colloidal suspension were
investigated by the zeta potentiometer. The point of zero charge of the suspension was shown near pH
5 and maximum zeta potential was -55[mV] near pH 11. Maximum agglomerate particles were
appeared near to the point of zero charge. The bending strength and water absorption of sintered
bodies were more than 8.35kgf/cm2, and less than 5.0% above 1100 oC respectively. In addition,
crystalline phase of sintered bodies were quarts and mullite. The micro-structure of the sintered body
has a uniform pore size and distribution.
Formation Mechanism of Nano AlN Powder by Gas-Reduction-Nitridation
Authors: Yamakawa T. , Tatami Junichi , Wakihara Toru , Komeya Katsutoshi , Meguro Takeshi , MacKenzie Kenneth
Published: March 2009

AlN powders were synthesized by gas-reduction- nitridation of γ-Al2O3 powders using
NH3 and C3H8 as reactant gases. AlN was identified from the products that synthesized at
1100-1400 oC for 120 min in the NH3-C3H8 gas flow, and it was confirmed that AlN can be easily
fabricated by the gas-reduction-nitridation of γ-Al2O3. The products synthesized at 1100oC for
120min contained unreacted γ-Al2O3. By the 27A1 MAS NMR spectra, Al-N bonding in the product
increased with an increase in the nitridation ratio of the tetrahedral AlO4 shoulder which decreased
prior to that of the octahedral AlO6 shoulder. It seems that γ-Al2O3 was preferentially nitrided from
AlO4 rather than AlO6. AlN nano particles were easily converted directly from γ -Al2O3 at a low
temperature because the AlO4 within γ-Al2O3was preferentially nitrided.
Synthesis and Properties of Titania Nanotube Doped with Small Amount of Cations
Authors: Sekino Tohru , Okamoto Takumi , Kasuga Tomoko , Kusunose Takafumi , Nakayama Tadachika , Niihara Koichi
Published: March 2009

We have investigated a synthesis of metal (Nb, V, Cr, Mn, Co) -doped titania nanotubes
using a solution chemical processing in order to control optical and electrical properties. Titania
nanotubes doped with a small amount of cations up to 1 wt% exhibited similar morphology and
XRD pattern as the pure titania nanotubes, however, color of nanotubes was changed depending on
the dopants. It was found that Cr, Mn and Co doped titania nanotubes formed new absorption bands
in UV spectra. On the other hand, electrical resistivity of doped titania nanotubes was lower than
that of pure titania nanotubes.
Fabrication of Nanoabrasive Grinding Wheels and Their Application to Grinding Silicon Wafers
Authors: Kim T.W. , Hyun Sang Hoon , Kim Joo Sun , Lee Jong Ho , Lee Hae Won
Published: March 2009

In the surface machining of brittle materials, there exists a transition from brittle to ductile
modes when the depth of cut is reduced below a critical size using ultrafine abrasive grains. Vitrified
grinding wheels containing ultrafine abrasives in the sub-micrometer to nanometer range were
fabricated by mechanochemically milling nanoabrasive particles and subsequent viscous sintering of
abrasive-binder composites. The grinding characteristics of the nanoabrasive grinding wheels were
evaluated for the fine grinding of silicon wafers in terms of a variety of variables. Preliminary wafer
grinding results are presented on material removal rate and surface quality of silicon wafers.
Tribological Property of Plasma Sprayed TiO2 Coating
Authors: Lee Soo Wohn , Du Hao , Chen Huang , Hur Bo Young
Published: March 2009

The sliding wear property of plasma sprayed TiO2 coatings with porosity of 4.2% and
5.4% mating against silicon nitride ball were comparatively investigated with a reciprocating
tribometer under dry conditions. The results indicate that the wear resistance of the TiO2 coating
with lower porosity is superior, which is attributed to its homogeneous microstructure and improved
microhardness. The morphologies of the wear tracks of the two TiO2 coatings, as well as wear
debris reveal the pore is the main location wear occur. The coefficients of friction of the two TiO2
coatings decrease with the increase of applied load, while the wear rates increase, which is
attributed to the difference of the dependence of microhardness on load between the coating and the
Si3N4 ball. No apparent dependence of wear resistance on sliding speed was found on these two
coatings.
Indentation Contact Deformation of 3Y-TZP at Elevated Temperatures
Authors: Muto Hiroyuki , Yamada R. , Matsuda Atsunori , Sakai Mototsugu
Published: March 2009

The contact deformation mechanisms of a superplastic ceramic, 3Y-TZP (3mol % yttria-partially stabilized tetragonal zirconia polycrystals) are examined in indentation creep tests at high temperatures. A large discrepancy between the uniaxial compression and the pyramidal indentation contact behaviors is observed. The indentation creep curves exhibit a hardening behavior, i.e., the penetration rate decreases as the penetration depth and/or the creep time increases. This fact implied that the cooperative grain-boundary sliding (CGBS) in a microscopically localized region, such as the sub-surface contact region beneath a pyramidal indenter, is very limited through the microscopic processes of localized grain interlocking.
Thermal Conductivity of Zirconia for Thermal Barrier Coatings: A Perturbed Molecular Dynamics Study
Authors: Yoshiya Masato , Matsumoto Mineaki , Harada Akihiko , Takeuchi Munetaka , Matsubara Hideaki
Published: March 2009

Thermal conductivity of pure and Y2O3-doped ZrO2 was calculated using a perturbed molecular dynamics method in order to analyze phonon scattering mechanism which is responsible for the reduction of thermal conductivity. Although absolute values of thermal conductivity were overestimated due to a simple model used in this study, relative values were in good agreement with experiment, which indicates that phonon scattering due to Y2O3 addition is reproduced well. It is found from quantitative analysis of the phonon scattering using the mean field theory that decrease of the thermal conductivity upon Y2O3 addition is attributed not only to the introduction of O2- vacancies but also to substitution of Y3+ ions for Zr4+ ions.
Preparation and Characterization of Titania Thin Films
Authors: Lu Chung Hsin , Huang Jen Hsien , Chen Hsieh Hsin , Huang Po Hsiung
Published: March 2009

TiO2 sol with steady suspension and high photocatalytic activity was prepared via a precipitation-peptization method. The XRD results indicate that the TiO2 sol exhibited an anatase structure. TiO2 films on woven fabrics (carbon, PET and Nylon), prepared via dip-coating with TiO2 sol, were characterized by XRD and SEM analysis. The dependence of the woven fabrics properties on the amount of TiO2 coated and photocatalytic activity were also studied. When the diameter of fibers is smalle, large quantity of TiO2 is coated on woven fabrics leading to an improvement in the photocatalytic activity. It is observed that the photocatalytic activity of TiO2 film coated on woven fabrics exceeds that of TiO2 film coated on common glass substrate with the same surface area.
Fabrication and Characterization of Various Calcium Phosphate Powders by Ultrasonic Spray Pyrolysis Technique
Authors: Wang H.J. , Jeong Young Keun , Oh Kyung Sik , Kim B.H. , Lee Seong Hee , Choa Yong Ho
Published: March 2009

To overcome the difficulty of preparing the stoichiometric single phase calcium phosphate materials, ultrasonic spray pyrolysis was used to fabricate various calcium phosphates. Effect of the initial Ca/P ratios and pyrolysis temperature were investigated in preparation of single phase materials. Also thermal stability of the obtained powders was estimated with the heat treatment in the air. Crystallinity of the powders was analyzed using XRD and FT-IR. The HAp and β-TCP powders with single phase could be obtained from their stoichiometric Ca/P ratios of 1.50 and 1.67, respectively. These single phase powders with good crystallinity and stoichiometry were stable with respect to heat treatment up to 1000oC. The particle size of these powders would be controlled by the concentration of starting solution.
Microstructures and Mechanical Properties of Fine-Scale Fibrous Alumina / Zirconia Bi-Phase Composite Fabricated by Co-Extrusion Process
Authors: Miyazaki Hiroyuki , Yoshizawa Yuichi , Hirao Kiyoshi
Published: March 2009

A bundle of feedrod composed of ordinary arranged alumina and zirconia green rods was co-extruded through a 6:1 reduction die. The volume fraction of zirconia phase was varied from 10 to 88 vol%. After the first co-extrusion, the individual pieces were bundled and co-extruded again, reducing the lateral size of each phase and multiplying the number of continuous monofilaments. After a 3rd extrusion step and sintering at 1600oC, crack-free composites with a fiber diameter of ~50 μm were obtained for all compositions. The fracture toughness of the composites was improved by introducing fine second phase filaments into the matrix. The maximum fracture toughness of 6.2 MPam1/2 was attained in the 3rd co-extruded composite which consisted of 53 vol% alumina and 47 vol% zirconia. Bending strength of the composites was almost the same as that of the monolithic alumina regardless of the composition.
Nanocomposite Formation in the Fe3O4-M (M=Al, Ti) Systems by Mechanical Alloying
Authors: Lee Chung Hyo , Lee Seong Hee , Lee Sang Jin , Choa Yong Ho , Kim Ji Soon
Published: March 2009

Nanocomposite formation of metal-metal oxide systems by mechanical alloying
(MA) has been investigated at room temperature. The systems we chose are the Fe3O4-M
(M=Al, Ti), where pure metals are used as a reducing agent. It is found that nanocomposite
powders in which Al2O3 and TiO2 are dispersed in a α-Fe matrix with nano-sized grains are
obtained by MA of Fe3O4 with Al and Ti for 25 and 75 hours, respectively. It is suggested that
the shorter MA time for the nanocomposite formation in Fe3O4-Al is due to a large negative
heat associated with the chemical reduction of magnetite by aluminum. X-ray diffraction
results show that the average grain size of α-Fe in Fe-TiO2 nanocomposite powders is in the
range of 30 nm. From magnetic measurement, we can also obtain indirect information about
the details of the solid-state reduction process during MA.
Synthesis and Densification of CNTs/Fe/Al2O3 Nanocomposite Powders by Chemical Vapor Deposition
Authors: Yoo Seung Hwa , Wang H.J. , Oh Sung Tag , Kang Sung Goon , Choa Yong Ho
Published: March 2009

CNTs/Fe/Al2O3 nanocomposites were prepared by thermal CVD and SPS methods. The dispersion of CNTs in the Fe/Al2O3 matrix were controlled by an attrition milling process. FESEM analysis revealed that the CNTs of 5 vol.% were homogeneously dispersed in the Fe/Al2O3. The effects of CNTs dispersion on the mechanical and electrical properties of the specimens were investigated. Fracture strength and electrical conductivity of 5 vol.% CNTs/Fe/Al2O3 specimen were measured at 641 MPa and 2.93 10-11 mS/m, whereas that of a 20 vol.% CNTs/Fe/Al2O3 specimen were 208 MPa and 8.46 10-7 mS/m, respectively. In comparison with an Al2O3 monolith, the specimen with 5 vol.% CNTs showed enhanced fracture strength and increased electrical conductivity.
Evaluation of Thermal Stability of Porous Material by Sintering Stress
Authors: Wakai Fumihiro , Shinoda Yutaka , Akatsu Takashi
Published: March 2009

The sintering stress is related to the thermal stability of porous structure. The sintering
stress for a given porous structure in equilibrium can be calculated by three methods theoretically;
the energy difference method, the curvature method, and the force balance method. The sintering
stresses by three different methods were exactly the same for the idealized porous materials in
equilibrium, in which the pore surface had a constant curvature at any point. The porous material
does not spontaneously shrink when the sintering stress becomes zero or negative. The sintering
stress will be used to design optimal porous structures with improved thermal stability.
Synthesis of WO3 Electrochromic Sensor by Sol-Gel Method and Characterization of Its Electrochemical and Optical Properties
Authors: Kim Chang Yeoul , Choi Jin Wook , Lim Tae Yeoung , Choi Duck Kyun
Published: March 2009

Electrochromic WO3 thin film was prepared by using tungsten metal solution in hydrogen
peroxide as a starting solution and by sol-gel dip coating method. XRD pattern showed that tungsten
oxide crystal phase formed at 400. In the view of electrochemical property, WO3 thin film which
was heat-treated at 300 and was amorphous had better than that of the crystalline phase.
Comparison of Adsorption Capability and Photocatalytic Activity for Methylene Blue Decomposition of LiInO2 with NaInO2
Authors: Wang Jun Hu , Nonami Toru
Published: March 2009

In the present study, Pt, NiO, and RuO2 fine particles as co-catalyst were loaded on the
LiInO2 surface by different methods for enhancing its adsorption capability and photocatalytic
activity for methylene blue dye (MB) decomposition. Clear adsorption capability and marked
photocatalytic activity for MB decomposition were confirmed on the co-catalyst loaded LiInO2
composite particles. Comparing with that of LiINO2, the previously reported NaInO2 photocatalyst
had stronger adsorption capability and higher photocatalytic activity. However, the adsorption
capabilities and the photocatalytic activities were separately in the same order of RuO2/AInO2 >
Pt/AInO2 > AInO2 > NiO/AInO2 and Pt/LiInO2 > RuO2/LiInO2 > NiO/LiInO2 > LiInO2 for the two
promising AInO2 (A = Li+ or Na+) photocatalyst.
Dielectric and Piezoelectric Properties of xPb(Ni1/3Nb2/3)O3 - yPb(Mn1/3Nb1/3Sb1/3)O3- (1-x-y)Pb(Zr0.48Ti0.52)O3 Ceramics
Authors: Sun Hua Jun , Chen Wen , Liu Xiao Fang , Xu Qing , Zhou Jing , Wang Hao
Published: March 2009

xPb(Ni1/3Nb2/3)O3-yPb(Mn1/3Nb1/3Sb1/3)O3-(1-x-y)Pb(Zr0.48Ti0.52)O3 ceramics have been
prepared by a columbite two-step method. NiNb2O6, MnNb2O6 and MnSb2O6 were used as
precursors to produce the pseudoquintnary system ceramics. X-ray diffraction (XRD) results
indicate that the pseudoquintnary system ceramics have a single-phase perovskite structure. The
piezoelectric and dielectric properties of the ceramics were investigated as functions of x or y. The
addition of Pb(Ni1/3Nb2/3)O3 makes the piezoelectric properties to become ‘soft’, while the
addition of Pb(Mn1/3Nb1/3Sb1/3)O3 makes the piezoelectric properties to be ‘hard’. The Curie
temperature (Tc) of the pseudoquintnary system decreases with the increase of Pb(Ni1/3Nb2/3)O3 or
Pb(Mn1/3Nb1/3Sb1/3)O3 contents. The preferred piezoelectric properties were obtained in the
composition with x=0.06 and y=0.06.
Composite Damping Ceramic Coatings by Polymer Impregnation
Authors: Patsias S.
Published: March 2009

The interest in the use of thermal barrier ceramic coatings as damping treatments has recently arisen
since they were shown to provide sufficient additional damping. Ceramic coatings can be applied
mainly by either Air Plasma Spraying (APS) or Electron Beam - Physical Vapour Deposition (EBPVD).
APS was used to deposit the specimens studied here. Previous research has shown that it is
possible to enhance their damping effectiveness by tailoring the deposition parameters.
This paper presents further work aimed at improving their damping effectiveness significantly by
introducing a second material in the ceramic coating; thus creating a composite system. This paper
covers the experimental findings of impregnating a ceramic damping coating with a number of
commercially available polymeric materials. The most promising case of a type of Polyurethane
provided over 40% improvement and was selected for further tests at various temperatures, ranging
from -40 to 150 􀁱C.
Furthermore, the damping and stiffness of ceramic coatings present amplitude-dependent behaviour
which was also taken into consideration when evaluating the composite system. Finally, the paper
concludes with a discussion of these promising findings as well as planned research into
understanding the physical mechanisms dissipating energy in this composite material.
Anelastic Properties of Mg+3vol.%Gr Prepared by Ball Milling
Authors: Trojanová Zuzanka , Bosse Michael , Ziegmann Gerhard , Mielczarek Agnieszka , Ferkel Hans
Published: March 2009

Internal friction in ultra-fine grained Mg with 3vol% of Graphite was measured by forced vibration method at low frequencies of 0.1, 0.5, 1.0, and 2.0 Hz over a temperature range from room temperature to 753 K with continuous heating. The specimens were prepared by milling procedure in an inert atmosphere and subsequent compacted and hot extruded. Two developed peaks in the internal friction spectrum were obtained at temperatures ≈ 350 K and ≈ 550 K. While the position of the first peak is frequency dependent, the second peak position is stable, independent of measuring frequency. The activation energy of the low temperature peak was estimated. In the light of internal friction measurements, the high temperature internal friction peak is attributed to the generation and motion of dislocations produced by the difference in the coefficient of thermal expansion between the Mg matrix and Gr phase at the matrix–particle interfaces.
Internal Friction of Hydrogenated Ti (Ni,Cu) Shape Memory Alloys
Authors: Ueura T. , Sakaguchi Takuya , Igata N. , Takeuchi Shin
Published: March 2009

Effects of hydrogen doping on the internal friction (IF) of ternary Ti50Ni50-xCux (x=15, 20,
25) shape memory alloys, prepared by rolling and annealing laminating Ti and Ni-Cu alloy sheets,
have been measured with a damping mechanical analyzer in a forced bending oscillation mode at
temperatures from 173K to 423K at three frequencies, 0.1, 1 and 5Hz. The effects of hydrogen
doping on IF are common to the three alloys: a hydrogen IF peak appears at around 260K; the IF
peak value (tanφ) increases rapidly with increasing hydrogen concentration up to tanφ=0.03 at
0.5at% and then decreases; the peak temperature also increases rapidly and then gradually decreases.
From the frequency dependence of the peak temperature, the activation energy E and the
pre-exponential factor ω0 have been analyzed to be E=0.6-0.7eV and ω0=1013-14s-1. The origin of the
hydrogen IF is interpreted to be the Snoek-Koester effect due to interaction of twin boundary
dislocations and segregated hydrogen atoms. Effects of hydrogen on mechanical properties of the
alloys have also been studied.
Effect of Chromium Addition on Damping Capacity, Mechanical Property, and Corrosion Resistance of Fe-18%Mn Alloy
Authors: Kim Jung Chul , Baik Seung Han , Jun Joong Hwan , Lee Young Kook
Published: March 2009

Effect of Cr addition on damping capacity, mechanical property, and corrosion resistance
of Fe-18%Mn martensitic alloy has been studied. Martensite start temperature (Ms) of the alloy
decreases linearly from 150 to 25 with increasing Cr content up to 15%. The damping capacity
decreases gradually from 27 to 23% in SDC with increasing Cr content from zero to 10%, and
decreases rapidly with further Cr content. The tensile strength of the alloy maintains a level of 60
/ regardless of Cr content with an elongation of 20 to 25%. Immersion test in 5% NaCl
solution leads to the result that the corrosion resistance of the alloy becomes excellent above 10%
Cr. From the above results, it is concluded that the optimum Cr content to improve the mechanical
property and corrosion resistance of the alloy with a lesser decrease in damping capacity is about
10%.
Influences of Si and Co Addition on Microstructure and Damping Capacity of Fe-Mn Alloy
Authors: Jun Joong Hwan , Lee Young Kook , Kim Jeong Min , Kim Ki Tae , Jung Woon Jae
Published: March 2009

Microstructures and damping properties have been investigated in Fe-23%Mn-(0~2)%Si and Fe-23%Mn-(0~2)%Co alloys, based on experimental results from metallography, X-ray diffractometry and vibration test in a flexural mode. The amount and number density of ε martensite are increased with an increase in Co content, resulting in the improvement of damping capacity. For the same ε martensite content, the higher the Co content, the greater the damping capacity. On the contrary, an addition of Si affects to decrease the amount and number density of ε martensite, giving rise to a decay of damping capacity. The decreased ε martensite content by the addition of Si would be attributed to an increase in critical driving force for the γ→ε martensitic transformation by solution hardening effect.
Relation Between Grain Boundary and Electrical Degradation of ZnO Varistors
Authors: Takada Masayuki , Yoshikado Shinzo
Published: March 2009

The effects of the electrical degradation characteristics and microstructure of Sb2O3-doped ZnO varistors were investigated by optical microscopy, X-ray diffraction (XRD) analysis, and voltage-current (V-I) characteristics analysis. The nonlinearity index α of the V-I characteristics of the Bi-Mn-Co-Sb2O3-doped ZnO varistors decreased with increasing Sb2O3 content after electrical degradation. The twin crystal of ZnO was formed by doping with Sb2O3. The number of twin crystals, of which two c-axes are perpendicular to the twin plane, increased and the number of twin crystals, of which c-axes are parallel to the twin plane, decreased with increasing amount of Sb2O3 doped. It is suggested that electrical degradation is affected by the combination of the orientation of ZnO grains containing twin planes and a double Schottky barrier may not be formed in the twin plane.
Dielectric Properties of Phosphate Glasses in the Region from 1 to 10 GHz
Authors: Fujino Shigeru , Kuwabara Makoto
Published: March 2009

Dielectric constants were measured for phosphate and silica glass systems in the frequency region of 1 to 10 GHz using the resonance cavity method. Compositional dependence of dielectric constant and tangent loss were discussed. The effect of the cations on the ε indicates that ε increases in the order, R:Mg <Zn<Ca<Sr<Ba and thus depends upon the ionic radius. The effects of Mg and Zn cations on the refractive index and dielectric constant were different from those of Ba,Sr, and Ca cations, that is Mg2+ and Zn2+ have coordination numbers of about 4 and would partially play a role similar to a silica- network in phosphate glasses.
High-Rate Electrode Properties of Li-Mn-oxide Synthesized by Reassembly of MnO2 Nanosheets for Li-Ion Battery
Authors: Suzuki Shinya , Takahashi Seijiro , Sato Keigo , Miyayama Masaru
Published: March 2009

High-rate lithium intercalation properties of the Li-Mn-oxide synthesized by the reassembly of
MnO2 nanosheets were examined. The colloidal suspension of MnO2 nanosheets was prepared by
the exfoliation of proton-exchanged form of layered manganese oxide through the reaction with
tetrabutylammonium hydroxide aqueous solution. The results of chemical analysis indicated that a
Li-Mn-oxide had a chemical formula of Li0.31MnO2·0.05H2O. The discharge capacity of a
Li-Mn-Oxide was 193 mAh/g initially, and decreased gradually during cycling. A Li-Mn-oxide
exhibited the discharge capacity of 79 mAh/g at the current density of 2 A/g, and it was 52 % of 151
mAh/g at the current density of 50 mA/g.
Oxygen Reduction Electrode Properties of the Ba(Ce,Gd,Ru) O3-δ Oxides at Low Temperatures
Authors: Toda Haruhiko , Yoshihara Kenji , Saito Morihiro , Kuwano Jun , Shiroishi Hidenobu
Published: March 2009

The O2-gas electrode (OGE) properties of the BaCe1-xGd0.2RuxO3-δ(BCGRx, x=0-0.45)
oxides and the BaGd1-yRuyO3-δ(BGRy, y=0.5-1.0) oxides were examined with the cell of
the type solid-state cell (OGE|BaCe0.8Gd0.2O3|OGE) below 300°C. Two single perovskite
phases, BCGR0.15 in the BCGR series and BGR0.5 in the BGR series, exhibited OGE
properties superior to those of known OGEs of Pt electrodes and La0.6Sr0.4Co0.98Ni0.02O3.
Oxide-ion currents of the order of over one hundred μAcm-2 not yet reported were
allowed to pass through the solid-state cell at low temperatures of ∼200°C.
Chemically Deposited (100)-Oriented BaTiO3 Films with Highly Concentrated Solution Using High Crystallinity BaTiO3 as a Buffer Layer
Authors: Guo Yi Ping , Suzuki Kazuyuki , Nishizawa Kaori , Miki Takeshi , Kato Kazumi
Published: March 2009

BaTiO3 films with thickness of ~1 2m were prepared by chemical solution deposition on
LaNiO3/Pt/TiOx/SiO2/Si substrate with a thin highly (100)-oriented and high crystallinity BaTiO3
thin film (~140 nm) as a buffer layer. The BaTiO3 films prepared by using a 0.5 mol/L solution have
high crystallinity and still show (100) preferred orientation. The electrical properties of the
(100)-oriented BaTiO3 films prepared by this process have been studied. A dielectric constant of
~910 and a loss tangent of ~3.5% (1 kHz) were obtained. The remanent polarization (2 Pr) and
coercive field (2 Ec) are 4.0 μC/cm2 and 35 kV/cm, respectively.
Investigation of Scintillation Screens for X-Ray Imaging
Authors: Kim Jung Min , Kim Ho Kyung , Cheong Min Ho , Cho Min Kook , Shon Cheol Soon , Lim Chang Hwy
Published: March 2009

Terbium-doped gadolinium oxysulfide (Gd2O2S:Tb) phosphor screen is the most popular
X-ray converter in diagnostic radiology. We have investigated the fundamental imaging performance
of Gd2O2S:Tb screens in terms of X-ray sensitivity and MTF (modulation-transfer function). The
measurements were performed for a wide range of coverages (34 – 135 mg/cm2) by using a
conventional film radiographic method. In addition, CsI:Tl having columnar structure was also
investigated.
A New Severity Index for Nondestructive Dynamic Analyses in Equinus Gait
Authors: Rim Yong Hoon , Kim Young Jin , Lee Sang Sik , Mun Joung H.
Published: March 2009

Equinus gait, defined as walking on one forefoot or both forefeet, has long been considered
an undesirable characteristic in patients with a variety of neuromuscular disorders. In the equinus gait,
the heel contact pattern is changed according to the severity, because an excessive ankle plantar
flexion instigates rearfoot lifting in patients. However, no biomechanical severity index exists to
evaluate the rehabilitation procedure of equinus gait. Therefore, we developed an SIEG (Severity
Index of Equinus Gait) for nondestructive evaluation of the equinus gait and to validate the index with
regard to 11 kinematic and kinetic factors of gait analysis. In this study, the 3-D heel contact pattern
was considered for the development of a severity index. In order to verify the result, we compared the
developed severity index values with ankle joint kinematic and kinetic factors in 3 test groups. As a
result, the average SIEG values ranged between 10.45 (Normal group) and 26.61 (Severe group) and
the highest correlation with regard to the 3 groups was shown in the developed severity index.
Additionally, we also presented a fuzzy model using Takagi-Sugeno-Kang(TSK) logic with regard to
the 12 factors in order to more accurately classify equinus gait.
Moment Prediction for Evaluating Stability of the Upper Cervical Spine Fixed with Wires Using Finite Element Analysis
Authors: Kim Hyo Shin , Kim Youn Soo , Mun Joung H.
Published: March 2009

This study was aimed at predicting moments with respect to diameters of wires for
evaluating stability of the upper cervical spine fixed with wires based on the finite element analysis. In
case of the severe atlanto-axial instability, several surgical methods have been tried and the posterior
fixation using wires has been widely used because of the sufficient stability and high rate of bony
adhesion. The diameters of wires applied in this study were 0.7 mm, 0.9 mm and 1.25 mm. 1.5 Nm is
the moment for the normal physiological range of motion of the upper cervical spine in cadaver
models. However, if this moment is applied to the occiput, an excessive load occurs at the
occipito-atlantal joint and clinical problems can break out realistically. Thus, it is necessary to predict
moments for evaluating stability with respect to diameters of wires. The results showed that 0.7 mm
wire allowed the biggest moment while 1.25 mm wire allowed the smallest moment. In addition, the
upper cervical spine fused with wires was stabilized effectively as the load increased.
Development of an Algorithm for a PZT Ceramic Foot Pressure Sensor
Authors: Lee Sang Sik , Shin Ki Young , Mun Joung H.
Published: March 2009

Currently available foot pressure sensors (FPS), which usually include a capacitive sensor
and a piezoresistive sensor, tend to exhibit characteristically slow response times. Therefore, we used
PZT (lead zirconate-titanate) ceramic in this study, as it responds more quickly than the
currently-used materials. We have developed an algorithm which can be applied to the PZT
ceramic-based measurement of foot pressure. This algorithm was also verified in experiments. In this
study, we fabricated the electronic circuits and a sensor on the basis of the newly-developed
algorithm, and then verified the algorithm experimentally.
Computer-Graphics Based Analysis of Human Foot Kinematics during the Gait
Authors: Choi Hyeon Ki , Kim Si Yeol
Published: March 2009

A computer-graphics based biomechanical model was constructed to investigate the
kinematics of foot joints during the stance-phase of walking. In the model, all joints were assumed to
act as monocentric, single degree of freedom hinge joints. To obtain the inputs to the model, the
motion of foot segments was captured during the gait by a four-camera video system. The model fitted
in an individual subject was simulated with these motion data. The ranges of motion of the first
tarsometatarsal joint and the first metatarsophanlangeal joint were 8 ∼13 and -13 ∼ 48
respectively. The kinematic data of joints were similar to those of the previous studies. Our method
based on the graphical computer model is considered useful for kinematic analysis of small joints
including foot joints. Also, the results of this study will provide important information to the
biomechanical studies which deal with human gait.
Binding Inhibition Assay Using Fiber-Optic Based Biosensor for the Detection of Foodborne Pathogens
Authors: Morgan Mark T. , Kim Gi Young , Ess Daniel , Kothapalli Aparna , Hahm Byoung Kwon , Bhunia Arun
Published: March 2009

Frequent outbreaks of foodborne illness have been increasing the need for simple, rapid and
sensitive methods to detect foodborne pathogens. Conventional methods for pathogen detection and
identification are labor-intensive and take days to complete. Some immunological rapid assays are
developed, but these assays still require prolonged enrichment steps. Biosensors have shown great
potential for the rapid detection of foodborne pathogens. Among the biosensors, fiber-optic methods
have much potential because they can be very sensitive and simple to operate. Fiber-optic biosensors
typically use a light transmittable, tapered fiber to send excitation laser light to the detection surface
and receive emitted fluorescent light. The fluorescent light excited by an evanescent wave generated
by the laser is quantitatively related to fluorophor-labeled biomolecules immobilized on the fiber
surface. A portable and automated fiber-optic biosensor, RAPTOR (Research International, Monroe,
WA), was used to detect Salmonella enteritidis in food samples. A binding inhibition assay based on
the biosensor was developed to detect the bacteria in hot dog samples. The biosensor and the binding
inhibition assay could detect 104 cfu/ml of bacteria in less than 10 min of assay time.
Detection of Metal Contaminants in Food Using High Tc SQUIDs Magnetometer
Authors: Tanaka Saburo , Fujita Hiroyoshi , Hatsukade Yoshimi , Nagaishi Tatsuoki , Nishi Kazuaki , Ota Hajime , Otani Takeyoshi , Suzuki Shuichi
Published: March 2009

A PC controlled food contaminant detection system for practical use was designed and constructed. The system we have developed is the High-Tc SQUID based system, which is covered with waterproof stainless steel plates and acceptable to HACCP (Hazard Analysis and Critical Control Point) program. The outer dimension of the system is 1500L mm x 477W mm x 1445H mm and the acceptable object size is 200W mm x 80H mm. This system employed a double-layered permeable metallic shield with thickness of 1 mm as a magnetically shielded box. The distribution of the magnetic field in the box was simulated by FEM; the gap between each shield layer was optimized before fabrication. Then the shielding factor of 732 in Z-component was achieved. This value is good enough to operate the system in a factory. As a result, we successfully detected a steel ball as small as 0.3 mm in diameter with a distance of 75 mm.