bluuebunny/crossref_metadata_2025 huggingface dataset:
A Multi-Scale Analysis for an Evaluation of the Mechanical Properties of Composite Materials
Authors: Imura Makoto , Kurashiki Tetsusei , Nakai Hiroaki , Zako Masaru
Published: March 2009

Fiber reinforced composite materials have been applied widely to many structures,
because they have some advantages like easy handling, high specific strength, etc. The numerical
method like finite element method has been applied to design and to evaluate the material properties
and behavior as the development of Computer Aided Engineering. It is very difficult to calculate with
accuracy not only in structural scale but also in detail material scale (for example, the order of fiber
diameter) by the traditional FEM, becausecompositematerials like woven fabric composites have the
geometrical complexityand the large difference between above mentioned scales. The development
of multi-scale analysis method is one of the major topics in computational mechanics. Mesh
superpositionis one of multi-scale analysis methods and is an effective method to solve the problems
which have the large difference between the structure scale and the reinforcement scale. We have
expanded the finite element mesh superposition method with 3 scales and have defined as M3
(Macro-Meso-Micro) method. In this paper, we have proposed a new approach method combined
with M3 method and homogenized method to obtain the mechanical properties and to simulate the
behavior of woven fabric composites. In addition, the elastic-plastic mechanics and the damage
mechanics have been introduced into M3 method to investigate the effects of matrix-crack on the
structural and material properties. From the numerical results, it is revealed that it is very useful for
the evaluation of mechanical properties of composite materials.
PEEK- and PTFE- Based Composites for Tribology Applications in a Range between Liquid Helium and Room Temperature
Authors: Friedrich Klaus , Klein Patrick , Theiler Geraldine , Ye Lin , Mai Yiu Wing
Published: March 2009

This study deals with the development of PEEK (polyetheretherketone) and PTFE
(polytetrafluoroethylene) based composites, optimized for low friction and low wear performance
under extreme environments. It is demonstrated that the incorporation of a harder polymer
component into PTFE (such as PEEK particles), a short fiber reinforcement (e.g. carbon fibers CF),
and internal lubricants (e.g. PTFE particles), helps to reduce the friction and to improve the wear
resistance over a very wide temperature range.
Effect of Impact Modifier on The Properties of Poly (Ethylene Terephthalate)-Organoclay Nanocomposites
Authors: Yilmazer Ulku , Alyamac Elif
Published: March 2009

The effects of component concentrations and addition order of the components, on the
final properties of ternary nanocomposites composed of amorphous poly (ethylene terephthalate)
matrix, organically modified clay, and an ethylene / methyl acrylate / glycidyl methacrylate (E-MAGMA)
terpolymer were studied. All formulations were prepared by melt compounding of the
components with a two-step mixing procedure in a corotating twin-screw extruder. Considering the
X-Ray Diffraction, SEM, impact and strain at break results, the best sequence of component
addition was the one in which PET was first compounded with E-MA-GMA, later this mixture was
compounded with the organoclay in a subsequent run. In this mixing order, the polymer-impact
modifier matrix mixture prepared in the first extrusion run has higher melt viscosity than pure PET,
thus this matrix can apply high shear stresses on the clay particles and delaminate the clay layers
resulting in the best mechanical properties.
Glass Transition Temperature of Phenolic-Based Nanocomposites Reinforced by MWNTs and Carbon Fibers
Authors: Yeh Meng Kao , Tai Nyan Hwa , Lin Yan Jyun
Published: March 2009

The multi-walled carbon nanotubes (MWNTs) and carbon fibers (CFs) were added to the
phenolic resin to fabricate MWNTs/phenolic, MWNTs/CFs/phenolic nanocomposites and
CFs/phenolic composites by hot press method. The differential scanning calorimetry (DSC) test was
performed for the above-mentioned three kinds of composites. The valley points on the slope of
endothermic responses correspond to the glass transition temperatures of the composites. The
MWNTs/phenolic nanocomposites had the lowest glass transition temperature among the three kinds
of composites discussed, which indicated a better thermal conductivity property of MWNTs.
Phenolic-based composites reinforced by different weight percentages of MWNTs and CFs were also
investigated. The tensile failure morphologies of nanocomposite specimens were examined using a
scanning electron microscope to evaluate the possible effects on the glass transition temperature of
nanocomposites..
Drawing-Induced Dispersion of Nanoparticles and its Effect on Structure and Properties of Thermoplastic Nanocomposites
Authors: Ruan Wen Hong , Rong Min Zhi , Zhang Ming Qiu
Published: March 2009

To prepare polymer nanocomposites with enhanced performance, well dispersion of
nanoparticles in matrices is necessary. In this work a new route that combines graft pre-treatment and
drawing technique with melt mixing was applied. That is, nano-SiO2 particles were firstly modified
by graft polymerization and then the grafted nanoparticles were melt-compounded with
polypropylene (PP) producing composites filaments via drawing. Finally, the filaments were injection
molded into bulk materials. The resultant PP based nanocomposites are much tougher than the
unfilled polymer as characterized by either static or dynamic test, besides showing a simultaneous
increase in strength and stiffness. Morphology studies indicated that drawing induced extension and
separation of the grafted nano-silica agglomerates in PP matrix during making the filaments are
frozen to a certain extent after nanocomposites manufacturing. In this way, the nanoparticles are well
distributed in the matrix and correlated with each other throughout the entire composites, which might
ensure an overall improvement of mechanical properties. Besides, β-crystal of PP developed in the
drawing process can be retained in the nanocomposites, which also contributes to the toughening of
PP. In view of these, the proposed drawing aided dispersion of nanoparticles might also be applicable
to the preparation of other nanoparticles/polymer composites.
Graft Polymerization of p-Vinylphenylsulfonylhydrazide onto Nano-Silica and its Effect on Dispersion of the Nanoparticles in Polymer Matrix
Authors: Cai Li Feng , Rong Min Zhi , Zhang Ming Qiu , Ruan Wen Hong
Published: March 2009

To promote dispersion of nano-silica in polypropylene (PP), a polymerizable foaming
agent p-vinylphenylsulfonylhydrazide was synthesized and grafted onto the nanoparticles via
free-radical polymerization. The results of thermogravimetric analysis (TGA) showed that the
sulfonyl hydrazide groups of poly(p-vinylphenylsulfonylhydrazide) acquired the desired thermal
decomposition ability, which might be related to their internal oxidation-reduction. Electron
microscopy observation indicated that the grafted nanoparticles exhibit greatly improved dispersion
in PP owing to the fact that the sulfonyl hydrazine groups on the grafted polymer inside the
agglomerates decomposed like blowing agent to form polymer bubbles, leading to rapid inflation of
the surrounding matrix that pulled apart the agglomerated nanoparticles during melting mixing.
In Situ Crosslinking Induced Structure Development and Mechanical Properties of Nano-Silica/Polypropylene Composites
Authors: Zhou Tong Hui , Ruan Wen Hong , Rong Min Zhi , Zhang Ming Qiu
Published: March 2009

In our previous works, a double percolation mechanism of stress volumes was proposed to
explain the special effects generated by small amounts of grafted nanoparticles. Accordingly, it is
inferred that strengthening nanoparticle agglomerates and enhancing nanoparticles/polymer matrix
interfacial interaction are the key issues to improve mechanical performance of the matrix polymer.
To confirm this idea, in-situ crosslinking was adopted to prepare nanocomposites by adding reactive
monomers and crosslinking agents during melt compounding of nano-silica with polypropylene (PP).
It was found that the grafted polymer chains were successfully crosslinked and chemically bonded to
the nano-silica forming crosslinked networks. Meanwhile, matrix molecular chains penetrated
through the networks to establish the so-called semi-IPN structure that interconnected nanoparticles
by the networks and improved filler/matrix interfacial interaction. As a result, the tiny nanoparticles
were well distributed in the matrix and the toughening and reinforcing effects of the nanoparticles on
the matrix were brought into play at rather low filler loading, as evidenced by mechanical
performance tests. Besides, β-crystal was detected in the nanocomposites experienced in-situ
crosslinking reaction.
Thermal Conductivity of Polyimide/Carbon Nanofiller Blends
Authors: Ghose Subrata , Watson K.A. , Delozier D.M. , Working D.C. , Connell John W. , Smith J.G. , Sun Y.P. , Lin Y.
Published: March 2009

In efforts to improve the thermal conductivity (TC) of Ultem™ 1000, it was compounded
with three carbon based nano-fillers. Multiwalled carbon nanotubes (MWCNT), vapor grown carbon
nanofibers (CNF) and expanded graphite (EG) were investigated. Ribbons were extruded to form
samples in which the nano-fillers were aligned. Samples were fabricated by compression molding
where the nano-fillers were randomly oriented. The thermal properties were evaluated by DSC and
TGA, and the mechanical properties of the aligned samples were determined by tensile testing. The
degree of dispersion and alignment of the nanoparticles were investigated with high-resolution
scanning electron microscopy. The thermal conductivity was measured in two directions using the
Nanoflash technique.
Effect of Nanofillers on Phase Separation Behaviour of Diblock Copolymer: A Molecular Dynamic Study
Authors: Zeng Qing Hua , Yu Ai Bing , Lu Gao Qing Max
Published: March 2009

Polymer nanocomposites are recognized as the next generation of polymer composites
due to their exceptional properties. Understanding the molecular origin of the reinforcement
mechanism is crucial to the development of such promising materials. This paper reports our recent
molecular dynamic study on clay-based polyurethane nanocomposites. The effect of clay platelets
on phase separation behavior of polyurethane, at the clay-polyurethane interface, is quantified in
terms of molecular interactions, structure and dynamics. The results show that the nanoconfinement
of polyurethane chains in clay gallery impedes the development of phase separation
commonly observed in bulk polyurethane. The absence of phase separation of intercalated
polyurethane is believed to be related to the competitive interactions among clay platelet,
polyurethane and surfactant.
Young’s Modulus of Nanohoneycomb Structures According to the Porosity
Authors: Choi D.H. , Lee C.W. , Lee P.S. , Lee J.H. , Hwang Woon Bong , Lee Kun Hong , Park Hyun Chul
Published: March 2009

Young’s modulus of nanohoneycomb structures in the vertical direction relative to the
pore (generally along the beam length) is measured according to the porosity from bending tests in
atomic force microscopy (AFM). The pore diameters of the nanohoneycomb structures are from
about 30 to 60 nm. To determine the Young’s modulus of the nanohoneycomb structures, the area
moment of inertia of the nanohoneycomb structure is determined according to the arrangement of the
pores. The area moment of inertia of the nanohoneycomb structure is found to be affected by the
porosity of the nanohoneycomb structures. The Young’s modulus of the nanohoneycomb structures
decreases as a function of the porosity in a large range.
Size Effect on Fracture Behaviours of Epoxy Composites with Micron and Nano Alumina Particles
Authors: Tzeng Shi Hua , Tsai Jia Lin
Published: March 2009

This research is aimed to fabricate the nano and micron particle reinforced composites as
well as to understand the particulate size effect on the mechanical behaviors of the composites. The
stiffness, strength and fracture toughness were investigated in this study. Spherical alumina particles
with diameters of 5 microns and 10-20 nano meters were dispersed respectively into the epoxy resin
using the mechanical mixer followed by the sonication. To measure the stiffness and strength of the
composites, coupon specimens were prepared and then tested in tension. On the other hand, the
fracture toughness was evaluated by performing three point bending tests on the single edge notch
bending specimens. Experimental results revealed that the Young’s modulus of composites basically
is not affected by particulate size; while, the tensile strength of the composites containing nano
particles is higher than that with micron particles. From the fracture tests, it was indicated that the
composites containing nano particles possess superior fracture toughness than the composites with
micron inclusions.
Functionalization of Multi-Walled Carbon Nanotubes Via UV/O3 and Silane Treatments
Authors: Ma Peng Cheng , Kim Jang Kyo , Tang Ben Zhong
Published: March 2009

This paper presents a method for chemical functionalization of CNTs through the
combined process of UV/O3 treatment and silanization process. FT-IR and TEM were employed to
characterize the changes in surface functionalities and morphology. The results indicate improved
dispersion and attachment of silane molecules on the surface of CNTs. Epoxy matrix nanocomposites
containing functionalized CNTs showed much better dispersion with associated higher mechanical
properties than those without functionalization. These findings confirmed the improved interfacial
interactions due to covalent bonding between the functionalized CNTs and epoxy resin.
Compression Molding of All-Thermoplastic Composites by Using Fiber Wastes
Authors: Kaneda Tomoaki , Kimura Teruo
Published: March 2009

In the textile industry, recently, it is urgent to develop the recycling system of the
polyester fiber waste which results from the manufacturing process of sythetic fabric. However,
most of the fiber wastes are destroyed by fire or buried underground. In this paper, the insulating
composites which consist of polyester fiber wastes and PLA films are molded by compression
molding method. In the process of preforming, the polyester fiber wastes are arrayed in
uni-direction, and PLA films are inserted among layers of the polyester fiber wastes as binder.
Namely, the polyester fiber wastes layers and PLA films are laminated alternately. In this paper,
pitch (distance among the fiber wastes) and number of layers of polyester fiber wastes are varied,
and the effect of pitch and number of layers of polyester fiber wastes on mechanical property and
thermal insulating propertiy of the composites are discussed. As the result, it is concluded here that
the melted state and the thickness of layers of PLA affect largely on the thermal conductivity and
the bending strength of the boards.
A Simple Synthesis of Silver Nanoparticles in Laponite Suspensions
Authors: Yang Yan , Huang Hai Tao
Published: March 2009

A simple method is described for preparing silver nanoparticles via photoreduction in
layered laponite suspensions without any additional reduction agent or heat treatment. The
properties of silver nanoparticles were studied as a function of the UV irradiation time.
Transmission electron microscopy (TEM) was employed to study the variation of particle shape,
size and size distribution. The crystal structure of silver nanoparticles was characterized powder Xray
diffractometry (XRD). The optical absorption spectra of silver nanoparticles were obtained by
ultraviolet-visible (UV-Vis) spectroscopy.
Dielectric Property of Cyanate Ester / Nano-TiO2 Particles or TiO2 Whiskers Encapsulated by Polyaniline
Authors: Tao Jie , Zhou Hui , Qin Qi , Cui Yi Hua
Published: March 2009

Nano-TiO2 particles or TiO2 whiskers encapsulated by polyaniline/cyanate ester
composites were fabricated by solution-mixing method. Then the dispersion of particles in cyanate
ester was observed with the aid of TEM. The effect of the content of particles or whiskers on the
dielectric properties of cyanate ester composites was investigated. As the content of the particles up
to 3% or the whiskers up to 7%, the dielectric loss of the composites achieved its maximum.
Optimization for the Maximum Buckling Loads of Laminated Composite Plates – Comparison of Various Design Methods
Authors: Honda Shinya , Narita Yoshihiro , Sasakir Katsuhiko
Published: March 2009

Structural plate elements in composite structures are typically fabricated by stacking
orthotropic layers, each of which is composed of reinforcing fibers and matrix materials. In this work,
three optimum design approaches are compared to clarify the advantages and disadvantages for
optimizing the buckling performance of laminated composite plates. The first approach is developed
recently by the authors, where the buckling load is maximized with respect to the lamination
parameters by a gradient method and then the optimum lay-up design is determined by minimizing the
errors between the optimum parameters and parameters for all possible discrete lay-ups. The second
approach is the layerwise optimization (LO) approach where the fiber orientation angle in each layer
is optimized step-by-step by repeating one dimensional search. The third one is a direct application of
a simple genetic algorithm (SGA). In numerical examples, three sets of results are compared to
discuss on the methodology for buckling optimization.
Superhydrophobic Micro- and Nanostructures Based on Polymer Sticking
Authors: Kim Dong Hal , Hwang Woon Bong , Park Hyun Chul , Lee Kun Hong
Published: March 2009

Superhydrophobic polytetrafluoroethylene (Teflon®, DuPont) sub-micro and
nanostructures were fabricated by the dipping method, based on anodization process in oxalic acid.
The polymer sticking phenomenon during the replication creates the sub-microstructures on the
negative polytetrafluoroethylene nanostructure replica. This process gives a hierarchical structure
with nanostructures on sub-microstructures, which looks like the same structures as lotus leaf and
enables commercialization. The diameter and the height of the replicated nano pillars were 40 nm and
40 um respectively. The aspect ratio is approximately 1000. The fabricated surface has a
semi-permanent superhydrophobicity, the apparent contact angle of the polytetrafluoroethylene
sub-micro and nanostructures is about 160 °, and the sliding angle is less than 1°.
Preparation and Mechanical Properties of Nanocobalt Coated Al2O3-TiC Composites
Authors: Yin Yan Sheng , Chen Shou Gang , Chang Xue Ting , Lau Alan Kin Tak
Published: March 2009

Al2O3-TiC composites were fabricated by hot-pressing Cobalt coated powders at low
temperature through liquid phase sintering. Cobalt coating layers effectively hinder the growth of
grain and harmful reaction between Al2O3 and TiC particles, which would improve the mechanical
properties of Al2O3-TiC composites. The hardness decreases with the increase of Co content and the
bending strength was enhanced to 782MPa owing to the grain refinement effect of Co phase. The
fracture toughness, about 9.23 MPa.m1/2, was measured for the composites containing 3wt% Co
sintered at 1550°C. SEM images of fracture surface show that the toughening effect should be
attributed to the conversion of fracture mode caused by the Co phase.
Optimization of Sound Pressure from Vibrating Laminated Rectangular Plates
Authors: Kawakami Takuma , Narita Yoshihiro , Sasakir Katsuhiko
Published: March 2009

Composite materials are frequently used in automobile and other moving vehicle
structures. External and internal sounds sometimes cause unpleasant effects on the users and
environment, and reduction of such sound is one of the key engineering problems. This study presents
an acoustic radiation analysis from forced vibration of laminated rectangular plates and proposes a
design approach to reduce the sound pressure from the plates. In the analysis the sound pressure at an
arbitrary point over the plate is derived and is used as an object function in the optimization. A set of
the fiber orientation angles is used as the design variable, and is optimized to minimize the sound
pressure at the designated point. It is shown in numerical examples that the optimum design for sound
pressure reduction is possible by the present approach.
Preparation and Properties of High Performance Nanocomposite Bipolar Plate for Fuel Cell
Authors: Yen Chuan Yu , Liao Shu Hang , Lin Yu Feng , Hung Chih Hung , Lin Yao Yu , Ma Chen Chi M.
Published: March 2009

The thin polymer composite bipolar plates (the thickness < 1.5 mm) for use in polymer
electrolyte membrane fuel cells (PEMFCs) containing vinyl ester resin, graphite powder,
organoclay have been fabricated by bulk molding compound (BMC) process. Organoclay prepared
by ionic exchange of montmorillonite (MMT) with three different Mw of diamine intercalating
agents was used to reinforce the mechanical properties of the composite bipolar plates. Results
indicate that the basal spacing and content of MMT varied with Mw of POP-diamines are critical in
determining the resultant mechanical properties for bipolar plates. The flexural strength and the
unnotched impact strength of the plate were ca. 38 % (from 30.21 MPa to 45.66 MPa) and ca. 30 %
(from 58.11 J/m to 80.21 J/m) higher than the pristine graphite plate, respectively, as the basal
spacing of MMT (2 phr) was increased from 1.71 to 5.43 nm. The limiting oxygen index (L.O.I.)
and the UL-94 test revealed that the bipolar plate possesses excellent flame retardant with L.O.I.
higher than 50 and UL-94-V0. In addition, the electrical conductivity of the bipolar plates with
different MMT contents and basal spacing of MMT is higher than 100 S/cm.
Electron Transport Property and Pressure Effects in Au1-xTixO3 Octahedral Potential
Authors: Yu Xiao Long , Wu Shu Xiang , Qiu Xia Yan , Liu Ya Jing , Li Shu Wei
Published: March 2009

The Green’s-function and the force- and energy-balance equations for steady states have
been used to study the electron transport and its pressure effect with the influence of impurities and
acoustic-phonons in Au1-xTixO3 octahedral crystal potential. The results show that there is a
minimum temperature range of electrons as the center-of-mass velocity of electrons increasing, and
external pressure effect plays an important role in the contributions of impurities and phonons.
Preparation and Properties of Bi0.5Na0.5TiO3-Ba (Hf,Ti)TiO3 Lead-Free Piezoelectric Ceramics
Authors: Tian Hu Yong , Chen Wan Ping , Wang D.Y. , Wang Y. , Zeng J.T. , Chan Helen Lai Wah
Published: March 2009

Lead-free piezoelectric ceramics based on bismuth sodium titanate (BNT) -barium hafnate
titanate (BHT) were prepared by a two-step synthesis process. The final BNT-BHT ceramics sintered
at 1180oC for 2 h in air showed a perovskite structure with high density. The morphotropic phase
boundaries (MPB) were found in BNT based piezoelectric ceramics with 8~10 wt% BHT in
composites. In the case of Bi0.5Na0.5TiO3-0.08BaHf0.05Ti0.95O3 ceramics, a maximum piezoelectric
coefficient d33 of 122.6 pC/N was obtained. The remnant polarization (Pr) and coercive field (Ec) were
measured and the relationship between ferroelectricity and the BHT fraction in the compounds was
investigated. The BNT-BHT ceramics were expected to be a new and promising candidate for
lead-free piezoelectric device applications.
Free Vibration Analysis of Composite Structure under Thermal Condition
Authors: Ren Jian , Liu Q.
Published: March 2009

A nonlinear thermal vibration characteristic of the laminate composite thin shell structures
under linear temperature field is investigated by finite element method (FEM). The natural
frequencies of the composite laminated thin shell structures with different boundary conditions and
stacking sequence are calculated and analyzed. Numerical results show that the natural frequencies of
the structure are affected by the temperature, boundary conditions and the stacking sequence; the
proper stacking angle can change the natural frequencies; the effect degree on the natural frequencies
of symmetric composite structures is different from that of the antisymmetric one. These conclusions
can provide some guidance to structure design and heat-resistant design of composite structures.
Molten Salts Synthesis of Relaxor Ferroelectrics PMN-PT Powders
Authors: Zhao Shi Xi , Li Qiang , Song Feng Bing , Li Chun Hong , Shen De Zhong
Published: March 2009

Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) solid solutions with composition near the morphotropic
phase boundary (MPB) (33mol% PT) were successfully synthesized by the molten salt synthesis (MSS)
method at 800°C for 30min using Li2SO4-Na2SO4 and NaCl-KCl molten salts as a medium of reaction,
respectively. The influences of processing parameters, such as temperature, time, and type of salts, on the
formation and the micrographs characteristics of the PMN-PT powders were discussion. It was found that
the PMN-PT powder obtained by the MSS method has a relatively uniform size distribution and a better
dispersivity of particle, and an average size of PMN-PT particles with smooth surface was around 0.3∼0.5
μm. With other conditions being kept same, chloride molten salt is more propitious to the formation of
PMN- PT solid solutions, and improving the compositional homogeneity of PMN-PT powders.
Fabrication and Characterization of Porous TiB2 Ceramic with Three-Dimensional Interconnected Skeleton
Authors: Hong Chang Qing , Han Jie Cai , Zhang Xing Hong , Zhang He Xin
Published: March 2009

Porous TiB2 ceramics with a three-dimensional interconnected skeleton were fabricated by
high temperature pressureless sintering from fine TiB2 powders. The microstructure of the porous TiB2
ceramic was characterized by the enhanced neck growth between the initially touching particles. This
neck growth was ascribed to the selective heating of TiB2 particles with different dimension. The porous
structure prepared by the high-temperature sintering exhibited higher bending strength and fracture
toughness in the present experiment. The improved mechanical properties of the sintered composites
were attributable to the enhanced neck growth by surface diffusion.
Study of Affecting Factors on Porosity in Gel-Casting Foam
Authors: Xiao Qun Fang , Ning Xiao Shan , Fu Ming
Published: March 2009

Foaming and gelation of slurry is a recently invented processing route for fabricating porous ceramic. According to the method, a mechanical stir process was introduced to the ceramic slurry added with surfactant, then initiator was added to induce fast gelation between organic monomers and ceramic powder, the green body was obtained after a subsequently drying process. At last, porous ceramic was fabricated after sintering the green body at high temperature. Effects of surfactant volume content and several stirring factors on porosity are studied in this paper. It results that there is a proportional relationship between porosity and Reynolds number which only changes when stir time varies, different slurry or surfactant volume content results in similar relationship between porosity and Reynolds number.
Effect of Al2O3 on the Phase Stability of Y-Ce-TZP/Al2O3 Composites at Low Temperature
Authors: Lin Xu Ping , Ma Jing Tao , Zhang Bao Qing , Lin Qiang
Published: March 2009

The mechanical properties and the phase stability in yttria and ceria stabilized zirconia
containing 0-20wt% A12O3 during aging in air (300°C) and in water vapor (150°C, 180°C, 200°C and
250°C) are investigated in this paper. It is found that water can greatly accelerate the degradation of
Y-Ce-TZP. The addition of Al2O3 to Y-Ce-TZP prevents the low temperature degradation in air. Also
Al2O3 particles can restrain the phase transformation of tetragonal to monoclinic in Y-Ce-TZP under
water vapor condition when the temperature is below 200°C.
Study on the Properties of Alumina Ceramics after Implanted by Titanium Ions with MEVVA Sources
Authors: Shi Feng , Miao He Zhuo , Peng Zhi Jian , Li Wen Zhi
Published: March 2009

HIP (hot isostatic pressed) high-purity alumina was modified by Ti-ion implantation in a MEVVA (Metal Vapor Vacuum Arc) implanter. The samples were implanted by Ti ions with nominal doses 5×1016 to 1×1018 ions/cm2 under ambient temperature. The effects of titanium implantation and the ion dose implanted on the microstructures and mechanical properties of the ceramics were studied. After implanted by Ti ions, the maximum nanohardness of the as-implanted ceramics were increased about 20%; the bending strength were increased about 22%; the life of the alumina cutting tools were about 2 times longer than before. The result showed that all the factors of the improvement of the ceramic surface states played an important role on the mechanical properties after implantation.
Effect of Sr/Ba Ratio on Dielectric Properties of BSTN Ceramics
Authors: Zhou Zong Hui , Cheng Xin , Du Pi Yi , Chang Jun , Huang Shi Feng , Lu Ling Chao , Ye Zheng Mao
Published: March 2009

The phase composition of (1-x)BaO·xSrO·0.7TiO2·0.3Nb2O5 (BSTN) composite ceramics was analyzed by XRD, and the effect of Sr/Ba ratio on the dielectric properties of BSTN was investigated by impedance analyzer. The results showed that any sample with different x value contained two phases-the perovskite phase and the tungsten bronze phase. The dielectric constants of BSTN basically decreased while the tanδ increased with the increase in x value. Both dielectric constant and tanδ decreased with the applied frequency increased for the same x value. There were two Curie points for BSTN composite ceramics. The first one belonging to the perovskite phase decreased with the increase in x value, but the second one belonging to the tungsten bronze phase kept almost constant at about 300°C.
Effect of Heat Treatment on the Microstructure and Mechanical Properties of Cf/SiC Composites
Authors: Zhou Xin Gui , Zhou Chang Cheng , Zhang Chang Rui , Cao Ying Bin , Zou Shi Qin
Published: March 2009

3D braided carbon fiber reinforced silicon carbide (3D-Cf/SiC) composites were fabricated by precursor infiltration and pyrolysis(PIP), with carbon coatings prepared by chemical vapor deposition (CVD) before PIP. The effect of 1873K heat treatment on the mechanical properties of Cf/SiC composites were investigated. The results showed that heat treatment before PIP can increase the density of composites and lead to excellent properties of Cf/SiC composites. The flexual strength of the Cf/SiC composites with one cycle of 1873 K heat treatment reached 571 MPa, shear strength 51 MPa, and fracture toughness 18 MPa⋅m1/2.
Synthesis of the Fiber Coating by FP-CVI Process
Authors: Zhou Qing , Dong Shao Ming , Zhang Xiang Yu , Ding Yu Sheng , Huang Zheng Ren , Jiang Dong Liang
Published: March 2009

To obtain high performance ceramic matrix composites (CMCs), fiber coatings are often
fabricated as the interphase between fiber and matrix. The SiC coating was synthesized at low
temperature and reduced pressure in the present experiment. SiC was derived from a gaseous
methyltrichlorosilane (MTS)/H2 precursor by chemical vapor infiltration (CVI). The thickness of the
coating was inspected by SEM. The correlation between the coating thickness and the depositing
conditions, i.e. the deposition temperature, the pressure, the deposition time per pulse and the pulse
number were investigated. Based on these work, the C/SiC double-layer coating was fabricated.
Microstructural Characterization of In Situ TiB Whiskers in Ti MMCs Fabricated by SPS
Authors: Feng Hai Bo , Jia De Chang , Zhou Yu , Meng Qing Chang
Published: March 2009

The in situ TiB whisker reinforced titanium matrix composites were prepared by mechanical
alloying followed by spark plasma sintering. X-ray diffraction, scanning electron microscopy and
transmission electron microscopy were used to characterize the microstructure of the TiB whiskers. The
effect of sintering temperature on morphologies of in situ TiB whiskers was evaluated. With the increase
of spark plasma sintering temperature, the average diameter of in situ TiB whiskers increased. The in situ
TiB whiskers exhibited a hexagonal shape with (100), (101) and (10 1 ) planes at the transverse section
and a growth orientation of [010]TiB direction.
Manufacturing of Polymer Matrix Composite Material Using Marble Dust and Fly Ash
Authors: Gürü Metin , Tekeli Süleyman , Akin Emin
Published: March 2009

The amount of marble dust occurred during machining and cutting of marble pieces and fly
ash emitted from coal power plant is rather high and these wastes create significant environmental
pollution. In fact, these wastes can be utilized in various industrial applications. In this study, various
amount of fly ash, marble dust and polyester as base material, methyl ethyl keton peroxid as hardener
and cobalt naphtanats as accelerator were used to produce polyester matrix composite material.
Mechanical properties of composite materials were investigated and the optimum values were
determined. In the first step of the manufacturing of composite material, the amounts of hardener,
accelerator and polyester were kept constant and only fly ash/marble dust ratio was changed. The
experimental results showed that while fly ash/marble dust ratio up to 1/3 was increased, the strength
and hardness of the composite materials increased. Thus, the composite materials with high strength
and hardness were produced. The optimum three point bending strength and hardness values were
30.42 N/mm2 and 98 Shore A, respectively. In the second step, the amounts of hardener, accelerator
and fly ash/marble dust ratio were kept constant and the effects of the change in the amount of
polyester were investigated. It was seen that the highest tree point bending strength and hardness were
obtained at polyester/filler (marble dust +fly ash) ratio of 0,38. The optimum three point bending
strength and hardness values were 32.78 N/mm2 and 99 Shore A, respectively.
Unusual Microstructures and Strength Characteristics of Cu/Ti3AlC2 Cermets
Authors: Zhai Hong Xiang , Ai Ming Xing , Huang Zhen Ying , Zhou Yang , Li Shi Bo , Zhang Zhi Li
Published: March 2009

Cu/Ti3AlC2 cermets prepared by pressless sintering a mixture of Ti3AlC2 and copper powders
were investigated. It was found that the Cu/Ti3AlC2 possesses an unusual microstructure made up of
sub-micro-sheet layered Ti3C2 and Cu-Al alloy within one Ti3AlC2 particulate. The fracture strength
measured by the three-point-bending manner is increased but the deformation rate is reduced with
increase in the volume content of Ti3AlC2 from 30 % to 90 %. The highest fracture strength reached to as
higher as 983.9 MPa, corresponding to an extreme strain of 2.64 %. The fracture in mode was changed
from brittle to ductile with reduce in the content of Ti3AlC2. The higher fracture strength can be attributed
to a stronger interface bond between Ti3AlC2 and Cu-Al phase. A significant network feature formed by
the Cu-Al alloy surrounding Ti3AlC2 particulates was observed from the fracture face.
Defect and its Influence on Mechanical Property of Titanium Diboride-Copper Matrix Composite
Authors: Xu Li , Han Jie Cai , Zhang Xing Hong
Published: March 2009

The TiB2-40Cu-8Ni composite prepared by combustion synthesis is investigated. Both 2D
digital radiography (DR) and 3D computed tomography (CT) are used to test the specimens nondestructively.
The result shows that ceramic phase aggregation is the main defect. Then the mechanical
properties of samples are assessed by means of three-point-bend test. It appears that mechanical
properties are related with the distribution of TiB2 phase and Cu phase. The scanning electron microscope
(SEM) is also used to observe the crack growth of the bending test sample.
Effect of Y2O3 on Properties of Al/Ti3SiC2 Composite
Authors: Zhang Zhi Li , Zhai Hong Xiang , Zhou Yang , Huang Zhen Ying , Ai Ming Xing
Published: March 2009

Al/Ti3SiC2 composite samples were prepared by pressless-sintering route with high purity of polycrystalline Ti3SiC2 and aluminum powders. As yttria Y2O3 being additives during sintering process, the interesting change is that impurities Al4C3, Al4SiC4 and Al3Ti phase which are familiar in products of reactions between Ti3SiC2 and aluminum disappeared and that is valuable to stability of Al/Ti3SiC2 composite in atmosphere due to hydrolyzation of Al4C3. Then the tribological properties of 50Al/ 45Ti3SiC2/5Y2O3 and 50Al/50Ti3SiC2 were investigated by sliding the composites block dryly against low carbon steel disk for the sliding speed 20 m/s and the normal pressure of 0.2~0.8MPa. It was found that with load higher, the friction coefficient of 50Al/45Ti3SiC2/5Y2O3 increased from 0.21 to 0.57 and then reduced to 0.48, which is a little higher than 50Al/50Ti3SiC2 on large scale of pressure except under 0.2 ~ 0.3 MPa, but meanwhile it is remarkable that its rate of wear maintained a nearly steady value about 1.40 × 10-5 mm3/N·m comparing with 50Al/50Ti3SiC2, which shows a valuable tribological properties called non-pressure dependence to frictional materials.
Grinding of TZP/Al2O3 Composite with Vitrified CBN Wheels
Authors: Li Zhi Hong , Zhang Y.H. , Han Bing , Zhu Y.M.
Published: March 2009

Advanced ceramics has many advantages and great potential of application, but its high machining cost resulted from its high hardness and brittleness limited its application. Grinding with superabrasives is the most suitable and effective way for machining of advanced ceramics. Grinding with vitrified bond CBN wheels is a developing direction of high efficient grinding for engineering ceramics. Grinding of the promising composite ceramics of TZP/Al2O3 with vitrified bond CBN grinding wheels was investigated in this paper. The results showed that higher material removal rates and satisfactory surface finish were achieved, CBN wheels with coarser grit size or with higher CBN concentration had higher grinding ratio. G-ratio increased with the increasing of wheel speed.
Study on Ferroelectric Properties of Nd-Doped Bi4Ti3O12 Thin Films Prepared by Sol-Gel Method
Authors: Sun Y.H. , Liu X.B. , Chen Min , Liu J. , Chen S. , Wan Z.M.
Published: March 2009

Nd-doped bismuth titanate Bi4-xNdxTi3O12 (BNT) thin films were fabricated on Pt/Ti/SiO2/Si
substrates by sol-gel method and spin-coating technique. The structures and the ferroelectric properties of
the films were investigated. Nd doping leads to a marked improvement in the remanent polarization (Pr)
and the coercive field (Ec). At the applied electric field of 260 kV/cm, Pr and Ec of the BNT film with
x=0.5 annealed at 650oC are 19 μC/cm2 and 135 kV/cm, respectively. Moreover, the BNT film with x=0.5
showed a fatiguefree behavior up to 3×1010 read/write cycles.
Fabrication of SiCN MEMS by UV Lithography of Polysilazane
Authors: Wang Hua Tao , Xie Zhi Peng , Yang Wei You , Liu Guo Quan , An Li Nan
Published: March 2009

A novel process with low cost to fabricate SiCN MEMS based on UV lithographic technique is present in this paper. The prepared MEMS are very promising to be used in high-temperature environments. By adding a photo initiator to the polysilazane precursor, the precursor becomes UV-sensitive and can be solidified upon exposure to UV light, which leads to the formation of UV photo lithographical patterns. Key issues of the fabrication process are investigated and various SiCN MEMS structures are fabricated by this technique.
Thermal Shock Resistance and Ablation Behavior of TiB2-Cu-Ni Composite via Combustion Synthesis
Authors: Yong Zhang , Zhang Xing Hong , Xu Qiang
Published: March 2009

TiB2-Cu-Ni cermet composite was fabricated by self-propagating high-temperature synthesis combined with Pseudo Hot Isostatic Pressing. The microstructure of the composite is fine and uniform. The thermal shock resistance and ablation behavior of the TiB2-Cu-Ni composite was investigated by heating it for twenty seconds using a plasma torch arc heater. Fatal breakup took place in the monolithic TiB2 ceramic once the plasma arc flow faced the surface of the ceramic. Only a small crack was found on the ablation surface of the TiB2-Cu-Ni composite. The thermal stress fracture resistance parameter, R, and the critical energy release rate GIC of TiB2-Cu-Ni composite are at the same order with that of the W/Cu alloy. It showed that the properties of thermal shock resistance and the ablation of the composite are good. The fraction of mass loss of the homogeneous composite was 2.32 %, which was similar to that of traditional W/Cu alloy. The volatilization of the metal binder and mechanical erosion was the main mechanisms of the ablation.
Microstructure and Properties of (Ti,W)(C,N)/(Ni,Mo) Cermets after a Heat-Treatment at High Nitrogen Pressure
Authors: Zheng Li Yun , Xiong Wei Hao , Zhou Feng Yun , Zhang Xiu Hai
Published: March 2009

In order to decrease the heat-treatment time and avoid particle growth during the post-sintering heat-treatment, the interaction of nitrogen with (Ti,W)(C,N)/(Ni,Mo) cermets was investigated at high pressure. Sintered (Ti,W)(C,N)/(Ni,Mo) cermets with different starting formulations were heated at 1000 °C using nitrogen pressures up to 110 MPa. At this temperature and nitrogen pressure the nitriding time for the formation of interaction zones more than 20 μm thick is decreased to 3 hours and no particle growth occurs. The heat-treatment leads to a dramatic improvement in surface hardness and a very small decline in transverse rupture strength of the (Ti,W)(C,N)/(Ni,Mo) cermets. The microhardness in the near-surface area shows a transition of the highest microhardness to a lower as the interior is approached.
Apatite Formation on the Surface of Dense HA/TCP in Animals' Serums
Authors: Deng Chun Lin , Wang Ying Jun , Wu Yao , Qin Ying De , Fan Hong Song , Chen Ji Yong , Zhang Xing Dong
Published: March 2009

Dense HA/TCP bioceramics were immersed in pure bovine serum, rabbit serum and dog serum to observe apatite formation. Deposited crystals were examined using SEM. Results showed that some needle-like crystals formed on surface of sterilized HA/TCP, and needle crystals developed into sheet crystals and stick crystals after ceramics were immersed in bovine serum and rabbit serum respectively. The growth of crystals was maybe affected by the content of calcium, various kinds of albumen and alkaline phosphatase in different serums and the different pH of serum.
FCVA-Synthesized Tetrahedral Amorphous Carbon Films for Biomedical Applications
Authors: Zheng Chuan Lin , Yang Wu Bao , Chang X.
Published: March 2009

Tetrahedral amorphous carbon (ta-C) films were deposited onto Si(100) wafers by using
filtered cathodic vacuum arc technique (FCVA). The influence of the negative bias voltage applied to
substrates on film structures was studied by Raman spectroscopy, X-ray photoemission spectroscopy
(XPS). The ta-C films showed maximal sp3 fractions 87%, the hardness and elastic modulus of the ta-C
film is 72 and 480 GPa, respectively. In vitro measurements of contact angle and platelet adhesion were
applied to evaluate the biocompatibility of the ta-C films in comparison with that of NiTi, 316L and pure
titanium. The results show that the ta-C films have hydrophobicity and exhibit better hemocompatibility
which are very suitable for biomedical applications.
Dielectric Characteristics of Doped Strontium Titanate within Broad Temperature Range
Authors: Li Long Tu , Wang Tian , Wang Xiao Hui , Zhao Jing Chang , Li Xian
Published: March 2009

Dielectric characteristics of strontium titanate based ceramics doped with samarium were
investigated within temperature range from –60oC to 150oC. XRD was used to identify the phase
compositions of the ceramics and the microstructures were characterized by SEM. Good temperature
coefficient of capacitance (TCC) was observed: TCC = +18% ~ −11% with high dielectric constant of
18000 and relative low dielectric loss. After further modification, the present ceramics might be
promising candidates for the multilayer ceramic capacitors applications at high temperature.
MicroCT Aided Scaffold Design and Preparation
Authors: Wang Xian Gang , Tian Jie Mo , Guo Zhi Ping , Zhang Chao Zong , Wang Chen , Dong Li Min
Published: March 2009

Bone repair method has run to a new stage of bone tissue engineering. Doctors use bone
scaffold to fill bone trauma and expect human regeneration ability to reconstruct bone trauma while bone
is degrading. Scaffold is essential to bone tissue engineering. Scaffold should introduce new bone with
scaffold’s conduction channel. But it’s still very difficult for scaffold to mimic fine structure of bone.
Ideal scaffold should have similar component and microstructure to natural bone, which makes it more
biocompatible and better to reconstructed bone. So we forward microCT aided design and preparation to
solve this problem. MicroCT outputs both shape and three-dimensional internal density information.
Then, we build computer model of scaffold with acquired microstructure. We fabricate scaffold that
mimics natural bone by 3D rapid prototype machine.
Microstructure and Crystallization Behavior of Glasses in the ZrO2-ZnO-Al2O3-SiO2 System
Authors: Li Xiao Dong , Tian Jie Mo , Wang Chen , Dong Li Min , Zan Qing Feng
Published: March 2009

Crystallization behavior of ZrO2-ZnO-Al2O3-SiO2 glass has been studied by differential thermal analysis, X-ray diffraction analysis and scanning electronic microscope. ZrO2 doped in the glass induces the phase separation effectively. The crystal phases obtained are gahnite (ZnAl2O4) and a small amount of ZrO2 phase. SEM photographs show that the crystal phases distribute uniformly in the glass ceramics and the grain sizes of glass ceramics after different heat treatment are less than 60nm.
Preparation of DLC Scratch-Resistant Coating on PC Glass Lenses
Authors: Su Bao Hui , He Zi Bo , Ran Jun Guo , Gou Li , Wang Fang Hu , Su Bao Yue
Published: March 2009

Resin lenses have substituted for glass lenses to be dominant productions in eyeglasses market
because of lightweight, anti-impaction and easy molding. However, the problem existed that the wear
resistance of resin lenses was inferior. In order to increase the wear resistance of resin lenses, we coated
DLC film on PC by the method of RF-PCVD, researched the influence of depositing power, gas
concentration, time on the performance of coating, chose the optimum technological parameters. The
component of coating was testified by XPS. The hardness and wear resistance were tested. The results
showed that DLC films deposited on PC could improve the wear resistance of material.
Investigation of YSZ Thin Films on Silicon Wafer and NiO/YSZ Deposited by Ion Beam Sputtering Deposition (IBSD)
Authors: Chen Yu Ju , Wei Wen Cheng J.
Published: March 2009

Ion-beam sputtering deposition is a physical deposited method which uses accelerated ionbeam
to sputter oxide or metal targets, and deposits atoms on substrate. Thin films of yttrium-stabilized
zirconia (YSZ) were deposited on Si (100) wafer and NiO/YSZ plate. Scanning electron microscopy and
transmission electron microscopy with EDS were employed to study the microstructural and chemically
stoichiometric results of the films and the crystal growth process by various heat treatments. X-ray
diffraction was also used to analysis crystalline phase of the YSZ films. The influence of different targets,
substrates deposited efficiency and the properties of the film will be presented and discussed.
Effect of Heat Treatment on the DC Conductivity and Activity Energy of Li2O-Fe2O3-P2O5 Glasses
Authors: Pan Ji Yong , Gong Jiang Hong
Published: March 2009

Iron phosphate glasses with composition of 20Li2O-32Fe2O3-48P2O5 (in mol%) was
prepared by melting, crushing and heat-treating process and the electrical properties were examined.
It was found that the sample heat-treated at a temperature close to the glass transition temperature
exhibit the maximum conductivity and the lowest activation energy, implying that heat-treatment may
play an important role in the electrical properties of the glasses.