bluuebunny/crossref_metadata_2025 huggingface dataset:
In Situ Formation of TiC Reinforced Intermetallic-Matrix Composite Layers Produced by Laser Cladding
Authors: Fan Ding , Zhang Jian Bin , Sun Yao Ning , Dai Jing Jie , Fu Rui
Published: March 2009

Laser cladding technique was used to form Ni3(Si,Ti) intermetallic composite coating reinforced by in-situ formation TiC particles on Ni-based superalloy substrate. The experimental results showed that an excellent bonding between the coating and the substrate was ensured by a strong metallurgical interface. The clad coating was very well and free from cracks and pores. By means of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD), the effect of Ti-C addition to the microstructure and microhardness of the coating was investigated. The microstructure of the coating was mainly composed of Ni(Si), Ni3(Si,Ti) and TiC. The average microhardness of the coating was improved with increasing the Ti-C content. The microhardness was up to 780Hv when Ti-C addition was 20 wt. pct, which was much greater than that of Ni-based superalloy substrate.
Manufacture and Microstructures of Fe-Cr-C Hypereutectic In Situ Composites
Authors: Zhi Xiao Hui , Xing Jian Dong , Gao Yi Min , Wu Xiao Jun , Cheng Xiao Le
Published: March 2009

In the present study, a Fe-Cr-C hypereutectic alloy was prepared from industry-grade materials
and subjected to modification and fluctuation, through which new types of particle reinforced composites,
hypereutectic in-situ composite, was generated. The structures of the composite modified or not with the
range of fluctuation addition from 0% to 2.8wt.%, were investigated. The primary carbides were refined
with the addition of modifying agents and fluctuations. Increasing the amount of fluctuation resulted in
finer primary carbides. At 1380oC, with the addition of modifying agents and 2.8wt.% fluctuation
addition, the structure was well modified.
Surface Behaviors of ELID Ground Engineering Ceramics
Authors: Shen Jian Yun , Lin Wei Min , Ohmori Hitoshi , Xu Xi Peng
Published: March 2009

In this study, grinding of Si3N4, SiC, and Al2O3 ceramics under the condition of electrolytic
in-process dressing (ELID) system was investigated. The surface appearances of these engineering
ceramics during the ELID grinding process were attentively observed to describe the formation of finely
finished surfaces. Based on the analysis of material properties and detailed micro-observation of ground
surfaces, it can be concluded that the material removal mechanism of engineering ceramic is closely
related to its mechanical properties. The silicon nitride ceramic was most easily machined to precision
surface among these three engineering ceramics.
Effect of Surface Roughness on Matching Properties between Ceramic Framework and Coating-Glass for Dental Applications
Authors: Chen Ji Hua , Zhang Bin , Jin Zhi Hao , Gao Ji Qiang , Zhao San Jun
Published: March 2009

This study was conducted to evaluate the influence of surface roughness on anchoring strength
between ceramic and coating glass. Commercial Vita alpha glass-ceramic was selected as the coating
glass, while the zirconia/alumina (Z/A) composite as the substrate. Anchoring strength between substrate
and coating-glass was tested, and microstructure of the junction was also observed. From the experiments
we can find the following results. There was significant difference in the mean strength of different
surface roughness groups and HF acid-etching also had a favorable effect on matching properties. The
highest amount of anchoring strength was occurred at the high scope of roughness after HF acid-etching
and surface roughness will also affect the microstructure of the junction. Therefore, we can draw the
conclusions that with the limit of this research, roughness will influence matching properties between
ceramic substrate and coating-glass, while hydrofluoric acid etching was also suggested in the matching
procedure. Testing matching properties between ceramic substrate and coating-glass should consider the
influence of surface roughness.
Characterization of Porous Calcium Phosphate Bioceramics Modified by Porosifier
Authors: Gou Li , Cheng Shun Qiao , Ran Jun Guo , Su Bao Hui
Published: March 2009

The porous structure of calcium phosphate ceramics is one of the essential conditions resulting in bone formation. The porous structure of biphasic HA/β-TCP ceramics was improved by adding microporous porosifer and the porous characteristics such as porosity, pore size and pore size distribution were determined by the mercury intrusion porosimetry, the cell culture in vitro and the animal experiment. By means of SEM and fluorescence decoration, cells were observed firstly attaching the edge of macropores of specimens and the wall of the macropores with micropores when co-cultured with HA/β-TCP ceramics. The specimens were also implanted in dorsal muscles of healthy dogs for 1.5and 3 months. More bone formation in the specimen with microporous porosifer was found by histological observation after taking out. It suggested that the micropores in the walls of macropores of bioceramics had important effect upon their osteoinduction.
Rheological Properties of an Injectable Calcium Phosphate Bone Cement and their Relationship with the Phase Evolution
Authors: Ye Jian Dong , Wang Xiu Peng , Wang Ying Jun
Published: March 2009

An injectable calcium phosphate bone cement was prepared by combining amorphous calcium
phosphate (ACP) and dicalcium phosphate dihydrate (DCPD) for use in non-invasive surgery in this work.
The effect of the conserving time on the viscosity, yield stress and injectability of the calcium phosphate
cement (CPC) pastes were studied. The results showed that as the conserving time of the pastes prolonged,
the viscosity and the yield stress of the pastes increased exponentially, and the injectability of the pastes
decreased. This resulted from the transformation of DCPD and ACP into hydroxyapatite via hydration
reaction. The results also indicated that the pastes still exhibited good injectability in even 15 min after
preparation of the CPC pastes.
Bone Formation in Non-Osseous Tissues of Biphasic HA/β-TCP Bioceramics Sintered by Different Ways
Authors: Ran Jun Guo , Gou Li , Su Bao Hui , Wang Fang Hu , Sun Lu Wei , Ji Jin Gou
Published: March 2009

In order to improve the bioactivity of calcium phosphate bioceramics, biphasic HA/β-TCP (BCP) bioceramics were prepared by the microwave sintering and the microwave plasma sintering. Bone-like apatite formation of the resulting samples was investigated in simulated body fluid (SBF). The samples were also implanted in dorsal muscles of healthy dogs for 1.5and 3 months. All samples after taking out were examined by histological observation. Bone formation in different sintering ways and temperatures was investigated in details. Better osteoinductivity was found in samples sintered by the microwave and microwave plasma instead of the conventional furnace, as well as by lower temperature (1050 oC) instead of higher temperature (1150 oC). It accounts for that the increase in degradability of materials sintered by microwave and microwave plasma or lower temperature leads to the better of bone-like apatite formation and bone formation due to fine grains and lower crystallinity.
Influence of Impurities on the High-Temperature Water-Vapour Corrosion of Environmental Barrier Rare-Earth Silicates
Authors: Maier N. , Nickel K.G. , Rixecker Georg
Published: March 2009

Corrosion experiments on a number of rare earth di-silicates containing Y, Yb and Lu have
been conducted in flowing air with 30 vol.% H2O at 1500°C. Nominally the corrosion rate is slower
by a factor 5 to 10 compared to silica. However, alumina impurity incorporation has a profound
influence on the process of corrosion as it masks not only the gravimetric results but also changes the
surface phase assemblages to contain rare earth garnets and liquid phases. It is presumed that silica
loss occurs under those conditions via the liquid phase and does not necessarily follow the same
kinetics as direct silicate corrosion. Furthermore, atmospheric silicon hydroxide saturation effects
contribute to the corrosion process. Currently all determined corrosion rates of rare earth silicates are
viewed as system specific only.
Influence of Agglomerate Size on the Properties of Al2O3-Al2Cu3 Multiphase Ceramic Coatings
Authors: Cui Hai Ping , Yan Jun , Du Shi Guo , Du Xin Kang
Published: March 2009

Al2O3-Al2Cu3 multiphase coatings were prepared on the surface of steel by reactive flame
spray. The binding strength, microhardness and abrasion quality of the coatings were measured and
analyzed. The influence of the agglomerate size on the properties of the coatings was emphatically
studied to choose suitable size range for Al-CuO reactive system. The results showed that coatings
prepared by using –150∼+250 meshes agglomerates exhibited good mechanical properties.
AFM Investigation of Nano Particle Incorporated Sb Doped SnO2 Films
Authors: Wang Li , Bi Wen Yue , Zhang Xing Dong , Yu Xin Gang , Bao Hong Quan , Zhao Hui Feng
Published: March 2009

Antimony doped tin oxide (ATO) thin films were deposited onto silica coated soda lime silicate substrate by the sol-gel method using Sb(OC4H9)4 and Sn(OC4H9)4 as the precursor materials. Conductive tin oxide nano particles of different particle size were added into the sols. The films were subjected to heat treatment at t=500) for about one hour. Film structure and surface morphology has been investigated by means of atomic force microscopy (AFM). Room temperature electrical resistivity of the films was measured using the conventional four probe van der paul method. The influence of incorporation of conductive nano particles on the electrical conductivity of Sb-doped tin oxide films was studied. The correlation between the microstructure and the film electrical property has been obtained. The status of the nano particles in the films has also investigated by FTIR spectroscopy.
Two-Steps Digital Image Correlation and Application to Studies of Micromechanics Behavior of Coating Interface
Authors: Chen Jin Long , Liu Quan Yu , Qin Yu Wen , Ji Xin Hua
Published: March 2009

In this paper, two-steps digital image correlation method is well advanced with the sub-pixel reconstruction in sub-image by utilizing the higher precision calculation of bicubic spline interpolation value method, and the accuracy of displacement is extended to better than 0.01 pixel, the strain resolution is limited to less than 0.0002 in micro-region. The experimental results show that the method of two-steps digital image correlation is an up-to-date technique to comprehensive investigations of base metal-coating composition at extremely small size scales. In the meantime, influence of crack in base metal perpendicular to interface on coating is directly observed, and the measurement of the residual compressive strain in base metal is performed according to different thickness of coatings. Lastly, the bond behavior between base metal and coating has been quantitatively analyzed, and the experimental results also prove the Ni-Lan coating is combined with base metal by toughened interface.
Preparation of Decorative Building Glass-Ceramics by Using Cracked-Glass Panel as Precursor
Authors: Zhou Jun , Wang Yan Xin
Published: March 2009

Depending on surface and crack crystallization mechanism, a new type of glass-ceramics as a
decorative building material has been obtained by using cracked-glass panel as precursor to replace glass
grains used in conventional sintering process. In the comparative and parallel experiment, cracked-glass
panels and glass grains were made from the same glass melt belonging to CaO-Al2O3-SiO2 family, and
were heat-treated parallelly and transformed into two types of glass-ceramics tagged as CG-GCs and
GG-GCs respectively. XRD patterns and SEM micrographs of CG-GCs demonstrate that cracked-glass
can deposit β-wollastonite. Properties tests show that the compactness of CG-GCs is higher than that of
GG-GCs, signifying that, in comparison to glass grains in conventional sintering process, using
cracked-glass panel as precursor in this study can reduce the porosity of end products. In addition, it is of
great interest that the polished surface of CG-GCs can exhibit excellent texture much different from
granular one of conventional GG-GCs.
Crystallization of Cordierite-Based Glass-Ceramics Adding with Fe2O3-TiO2
Authors: Wang Shu Ming , Liang Kai Ming , Mei Le Fu , Zhou Feng
Published: March 2009

The effect of Fe2O3-TiO2 mixture additives on the crystallization behaviour of a parent glass
with composition located in the primary field of cordierite within the MgO-Al2O3-SiO2 system has been
examined. The crystallization behaviour of the glass was determined by differential thermal analysis
(DTA) and X-ray diffraction (XRD). The microstructure was characterized by scanning electron
microscopy (SEM). The results show that additives of Fe2O3-TiO2 can lower the temperature of the
crystallization peak (Tp) and promote crystallization of the parent glass. By controlled thermal treatment,
the main crystal phase obtained was Fe2+substituted α-cordierite. The approach outlined in this paper to
obtain heterogeneous ion substituted cordierite glass-ceramics is useful to develop infrared radiation
material with good properties.
Synthesis of Glass Ceramic from Goldmine Tailings
Authors: Wu Ren Ping , Chen Yang Guo , Gu Ying Yun , Zhang Tian Ran
Published: March 2009

Glass ceramic was successfully synthesized using goldmine tailings as main raw material. The
frit preparation and molding techniques, and the nucleation and crystallization processes were discussed.
The results showed that only one crystalline phase, idiomorphic diopside, was formed in shapes of small
columns and grains. The optimum temperatures for melt, sintering, nucleation and crystallization were
1350°C, 1160°C,750°C,and 860°C, respectively.
Clay Minerals as a Feasible Additive to Stabilize Cadmium in Contaminated Soils
Authors: Hu Zhen Qi , Yang Xiu Hong , Zhang Ying Chun
Published: March 2009

The adsorption behavior of clay minerals in cadmium contaminated soils has been studied in
order to remedy soils contaminated with this metal in this work. The results show that Langmuir model
best describes the adsorption of Cd2+, and the maximum sorption values of 8.45 mg/g for bentonite,
5.69mg/g for sepiolite and 10.57mg/g for attapulgite are obtained at pH 5-6. In addition, the effect of clay
minerals amendment on a highly cadmium contaminated soil has been studied by means of pot
experiments. The results indicate that the metal concentrations in shoot and root of plant decreased with
addition of clay minerals to soil (1%), and the highest decrease value of metal concentrations is obtained
in the soils added by attapulgite amendment.
Preparation of Rare-Earth Element Doped Titanium Oxide Thin Films and Photocatalysis Properties
Authors: Jia X.L. , Wang Y. , Xin R.S. , Jia Quan Li , Zhang Hai Jun
Published: March 2009

Rare-earth doped porous nanocrystalline TiO2 films were prepared via sol-gel method. The effect of preparation conditions on the properties of the resulting thin films, such as structure, surface topography and photocatalysis properties was analyzed. It indicated that appropriate doping of rare-earth element improves the photocatalysis ability of the thin titanium oxide films. The thin titanium oxide films have good photocatalysis properties in visible light region because of the red shift of energy level. It also revealed that uni-doped of cobalt is better than that of cobalt and lanthanum, while co-doping of cerium, cobalt and lanthanum may cause the best photocatalysis properties.
Preparation of WOx-TiO2 and the Photocatalytic Activity under Visible Irradiation
Authors: Song Hai Yan , Jiang Hong Fu , Liu Xing Qin , Jiang Yin Zhu , Meng Guang Yao
Published: March 2009

Nanocrystalline tungsten oxide doped titanium dioxide (WOx-TiO2) powders were prepared by
TiCl4 hydrolysis and characterized by XRD, XPS, UV–Vis absorption spectra and TEM. Results showed
that WOx not only hindered the growth of TiO2 particles but also greatly increased the transformation
temperature (>800 oC) from anatase to rutile during sintering; the dominant fraction of tungsten oxides
was non-stoichiometric tungsten oxide (WxOy) with Wn+ (4<n<6), which could easily substitute Ti4+ in the
lattice of TiO2. The light absorption band of TiO2 changed from the near UV to the visible light range
(2.68 eV in 1.0 %WOx-TiO2) because of the tungsten impurity energy level induced by WxTi1-xO2. The
photocatalysis experiments demonstrated that the MB in aqueous solution was successfully degraded
within 1h using WOx-TiO2 with an optimal WOx dosage of 1% under visible light irradiation.
Preparation of Conductive Composite Particles by Impact Coating Process
Authors: Hao Xiang Yang , Gai Guo Sheng , Yang Yu Fen , Zhang Yi He , Nan Ce Wen
Published: March 2009

PCS (particle composite system) is a kind of dry coating equipment. The PCS process involves
encapsulating UHMWPE (ultra-high molecular polyethylene) particles with a layer of SCB (super
conductive carbon black) or ACB (acetylene black), and subsequently compacting these CB-encapsulated
UHMWPE powders by compression molding to manufacture conductive polymer composites
respectively. Morphologies of these composite particles were investigated by SEM. By SEM, we can see
the conductive networks of CB in polymer composites. Coating-molding process with PCS can be used to
form network structure in ceramics and metal as well.
Preparation and Some Properties of Ni-TiN and Ni-TiC Nanocomposite Particles by DC Arc-Plasma
Authors: Okuyama Hideo , Ohno Satoru , Sakka Yoshio
Published: March 2009

Composite nanoparticles of Ni-TiC and Ni-TiN were prepared by an active plasma-metal reaction method. The structure and morphology were evaluated by X-ray diffraction and transmission electron microscopy observations. The morphology of the composite particles is dice-like or dumbbell-like, where the outer sides are metallic and the inner part of the rod (or dice)-like structure is TiC or TiN. The formation mechanism of the composite particles is considered by analogy to the VSL mechanism. The thermal stability of the nanocomposite particles is vastly superior to that of the metal particle. The excellent catalytic property of the Ni-TiN composite particle was confirmed when compared to the well-known Raney Ni particle and mixed particles of Ni and TiC.
Effects of Rare Earth Gd Doping on Ferroelectric Properties of PbZr0.52Ti0.48O3 Thin Films Prepared by Sol–Gel Methods
Authors: Sun Qiu , Song Ying , Wang Fu Ping
Published: March 2009

The Pb(Zr0.52Ti0.48)O3 thin films with 0-2at.%Gd dopants (denoted as PGZT) were prepared on
Pt/Ti/SiO2/Si substrates by a sol-gel technique and a rapid thermal annealing process. The structures of
PGZT films were characterized and the ferroelectric properties such as P–V loop, C–V and I–V
characteristics were investigated. Improved polarization (2Pr = 46.373 μC/cm2) and the low leakage
current (J = 1.5×10-9 A/cm2 at the electric field of 400 kV/cm) were obtained in the PZT thin film with
1at.% Gd dopant, which was better than that of the pure PZT thin film (2Pr = 39.099 μC/cm2, J =
4.3×10-8A/cm2). With the Gd contents up to 2at.%, a decreased remanent polarization was found.
Synthesis and Characterization of La2(MoO4)3 Microcrystals via Hydrothermal Microemulsion
Authors: Xu Yun Peng , Jiang Dan Yu , Liao Yi Kun , Shi Jian Lin
Published: March 2009

La2(MoO4)3 microcrystals with rodlike morphology have been successfully grown through hydrothermal microemulsion process at 180°C, pH =9 and 12 h. Quaternary microemulsion is composed of CTAB/water/hexane/n-pentanol. The obtained sample is characterized by means of XRD, FESEM, TEM. Formation mechanism is preliminarily discussed.
Preparation of PPy Nanowires and its Amperometric Response to Nitrate
Authors: Zhang Xiu Ling , Wang Ji Xiao , Wang Zhi , Wang Shi Chang
Published: March 2009

Polypyrrole(PPy) nanowires were prepared by template-free method electrochemically. The effect of process parameters on the morphology of PPy was investigated. The electrocatalytic effect of PPy nanowire modified electrodes was characterized by its amperometetric response toward nitrate ions. The experimental results indicated that the process parameters of the modified electrodes such as concentration of pyrrole monomer, concentration of support electrolyte (LiClO4), and the pH of buffer solution have significant effects on the diameter the length and smooth of PPy nanowires, and thus have obviously effects on electroreduction current density of nitrate ions. Under the optimized conditions, the PPy nanowire modified electrodes have high electrocatalytic activity toward nitrate electroreduction.
Microstructure Control and Phase Structure Study of Porous Alumina Membrane
Authors: Tian Yu Ming , Xu Ming Xia , Liu Xiang Zhi , Ge Lei , Zhang Ping
Published: March 2009

A two-step anodization process was used to fabricate wide-range highly ordered porous anodic alumina membrane (PAA) in the electrolyte of oxalic acid through different anodic voltages. The effect of anodic voltage, pretreatments and pore-expanding time on the microstruture of PAA membrane was also studied in the process of two-step anodization. In a certain range, with the increase of anodic voltage, the pore diameter almost increases linearly while the pore density almost decreases linearly. The PAA template with anneal and electropolishing process has better regularity. In a certain time range, the pore diameter increases obviously with the pore-expanding time. It was demonstrated by XRD that the crystal constitution of the PAA without heat treatment was polycrystalline structure which contained Baehmite phase (Al2O3.H2O), Gibbsite phase (Al2O3.3H2O) and θ-Al2O3 phase. After heat treatment at 500°C for 0.5h, only the θ-Al2O3 phase was retained.
On the Grain Size Distribution of MnO Doped ZnO Ceramics
Authors: Li Shu Ai , Liu Da Nian , Gong Jiang Hong
Published: March 2009

A series of MnO-doped ZnO with different grain sizes and grain morphologies were prepared
by sintering the samples at different temperatures for different holding times. The grain size distribution
for each sample was determined. It was found that, although the grain size increases and the grain
morphology varies with the sintering temperature and/or the holding time, the normalized grain size
distribution keeps invariable.
Preparation of Composite Ceramics of NiFe2O4/PZT by Sol-Gel Method and their Magnetoelectric Effect
Authors: Gong Wei Hua , Li Ming , Shi Zhan , Deng Hai Jin , Nan Ce Wen
Published: March 2009

The precursor powder of lead-zirconate-titanate (PZT) and NiFe2O4 (NFO) was prepared
using one step sol-gel method. The dry powders got after a series of processes were sintered via a
conventional ceramic solid-state reaction technique. All the diffraction peaks in the XRD patterns of
the composites can be readily indexed to NFO and PZT, respectively. The SEM micrograph shows
two different phases of PZT and NFO distinctly and the particle size of NFO was about 2~4 μm. The
magnetoelectric (ME) coefficient, dielectric constant, piezoelectric constant, magnetic hysteresis
loops of the samples were measured. The dc magnetic Hdc resulting in the maximum ME coefficient
varies from 0.65kOe to 1.0kOe with the increase of the NFO volume fraction. The maximum
magnetoelectric coefficient of 6.15Vcm-1Oe-1 was obtained at resonance frequency of 289.8kHz, dc
magnetic intensity of 0.8kOe and NFO volume fraction of 0.25.
Cyclic Fatigue of Alumina Ceramics as Evaluated by Modified Small Punch Tests
Authors: Xiong Zhi , Jiang Wan , Wang Lian Jun , Shi Ying
Published: March 2009

Fatigue behaviors of conventional alumina ceramics in cyclic loading with hemisphere and
cylinder punches are investigated with modified small punch (MSP) tests. Residual strengths are used to
quantify the degree of fatigue damage. The dependences of the residual MSP strength on loading mode,
cyclic loading magnitude, frequency, and puncher shape have been discussed in detail. Fatigue behavior
studies could be very convenient and effective because MSP tests could perform the cyclic loading and
then evaluate the residual strength consistently and effectively.
Erosive Wear Performance and Mechanism of Engineering Ceramic Materials
Authors: Liu Juan , Qi Long Hao , Xu Hong Yuan , Luo Xian Wu
Published: March 2009

A slurry pot tester was used to evaluate the erosion behavior of alumina (Al2O3), zirconia toughened alumina (ZTA), and silicon nitride ceramics. The eroded surface of sample was studied by scanning electronic microscope and the primary erosion wear mechanisms for ceramic materials were analyzed. On the same experimental condition, erosion wear resistance of materials follows this rule: Si3N4>ZTA>Al2O3. The key factor affecting erosive wear performance of ceramics is their microstructure. The primary erosive wear mechanisms for Al2O3, ZTA and Si3N4 ceramics are lateral crack propagation, whole grains pulled out and plastic deformation. The erosive wear performance of Si3N4 ceramic is the best in this experiment, due to their microstructure morphology with elongated grains.
Lambdoidal Layup of Aragonite Sheets in Conch Shell
Authors: Chen Bin , Peng Xiang He , Wu Xin Yan
Published: March 2009

The SEM observation on a conch’s shell shows that the shell is a kind of laminated bioceramic composite composed of aragonite layers and organic matrix. Each aragonite layer is parallel with the surface of the shell and consists of many thin aragonite sheets. These aragonite sheets are perpendicular to the layer where they are located. The observation also shows that the orientations of the sheets in different layers are different and these aragonite sheets compose various layups. A kind of lambdoidal layup is found. The maximum pullout force of the lambdoidal layup is analyzed based on its representative model. The result shows that the lambdoidal layup can markedly increase the pullout force of the layup and improve the fracture toughness of the shell.
Electronic Structure Study of Ni/Al2O3/Ni from First-Principles
Authors: Shang Jia Xiang , Guo Meng Qiu
Published: March 2009

The electronic structure and magnetic properties of Ni/Al2O3/Ni tunnel junctions with
O-terminated and Al-terminated interface models are investigated by first-principles discrete variational
method with the local-spin-density approximation. The results show that the interface atomic has an
important effect on interface electronic state and spin polarization as well as TMR ratio. For the
O-terminated and Al-terminated interface models, spin polarization at Fermi level of Ni layers exhibit
negative. It is found that absolute value of spin polarization as well as TMR ratio of Al-terminated
interface models is much larger than that of O-terminated interface, which shows over-oxidization of Al
layer could deteriorate magnetoresistance properties.
Study of Carbonizing Processes for Sintered Dolomite
Authors: Xue Jing Hua , Han Min Fang , Wang Qing Yun
Published: March 2009

It is the easy and widely used way to make light calcium carbonate and magnesium carbonate from dolomite by carbonizing process. During this process, the dolomite is calcined at different temperature, from 700°C to 950°C to get the mixture including either calcium carbonate and magnesia or calcia and magnesia. Then the mixture is blended with water in different temperature from room temperature to 80°C. As a result, it is supposed to get calcium hydroxide and magnesium hydroxide, but XRD analysis reveals that it is not accord with the theory. Magnesium hydroxide can not be obtained during this reaction. After the carbonization process, the calcium carbonate and a kind of mixture which is composed with different crystal phase of Mg5(CO3)4(OH)2[H2O]4 have been produced, instead of magnesium carbonate. The magnesia is gotten when the mixture is calcined at 450~750°C.
Structural Micro-Layered Ceramics with Surfaces under Tension and Compression with Increasing Apparent Fracture Toughness
Authors: Kübler Jakob , Blugan Gurdial , Jelitto Hans , Schneider Gerold A. , Dobedoe Richard
Published: March 2009

Two different designs of high fracture toughness micro-laminate ceramics were produced containing 50 μm thick Si3N4 layers and 100 μm thick Si3N4 + TiN layers. The first design with external tensile layers had a predicted maximum apparent fracture toughness of 10.5 MPa m1/2. The second design with external compressive layers had a predicted maximum apparent fracture toughness of 18.0 MPa m1/2. The fracture toughness of these micro-laminates was tested by the SEVNB method. A stiff testing machine was used to measure the R-curve behavior by observing crack growth in single notched specimens. A soft testing machine was used to measure the R-curve behavior using several specimens with notches at different depths.
Research on Morphology and Phase Structure of Al/Cu Interfaces Formed by Explosive Cladding
Authors: Li Yan , Wei Shi Zhong , Long Rui
Published: March 2009

The morphology and phase structure of Al/Cu explosive compounded interface were observed by scanning electron microscope, high-resolution transmission electron microscope and X-ray energy spectrometer. The results reveal that the interface of Al/Cu appears wave-like structure, with an average wavelength of 1.0mm and crest height of 0.3mm. Every wave has its front-nest. The wavelike interfaces are composed of microcrystal compound layer, non-crystal and nanocrystal. Several kinds of compounds such as Al9Cul2, Al4Cu9, Al2Cu, η-AlCu, β-AlCu3 and unidentified phase structure were found in Al/Cu interface. There are some bent lattice fringes around the front-nest. The research of microstructure in anchoring area revealed the nature of explosive cladding in metallurgical anchoring.
ZrO2-Ni Functional Gradient Bonding Interlayer
Authors: Polanco Raquel , Miranzo Pilar , Osendi María Isabel
Published: March 2009

A functional gradient (FG) layer based on Ni-ZrO2 (3mol% Y2O3) was obtained by
spraying diluted organic suspensions with an airbrush. The different layers were sequentially sprayed
onto Y-TZP and Ni substrates, in 25 vol.% compositional steps. Afterwards, two ZrO2 bulk pieces as
well as ZrO2 and Ni adherents were successfully joined using this type of FG structure as an interlayer.
The microstructure and the possible reactions between the ZrO2 and Ni phases were analyzed. The
porosity of each layer was evaluated by micro-hardness measurements.
Characteristics of Surfactant-Zirconium Phosphate Composites with Expanded Interlayer Separation
Authors: Shi Shi Kao , Zong Rui Long , Liu Ying , Wang Yue Hui , Zhou Ji
Published: March 2009

Surfactant-zirconium phosphate composites were prepared by surfactant cetyltrimethylammonium bromide intercalating to α-zirconium phosphate. The interlayer spacing of the lamellar structure was greatly expanded to 39.6 Å, as compared to 7.6 Å of α-zirconium phosphate. The molar ratio of surfactant to α-zirconium phosphate in the composites was found to be 1/1.46. The expanded interlayer separation is beneficial for complicated guest molecules intercalating to the galleries of the composites.
Development of Functionally Structured Materials: Ceramic Photonic Crystals and Fractals
Authors: Miyamoto Yoshinari , Kirihara Soshu , Hino K. , Kanaoka H. , Takeda Mitsuo Wada , Honda Katsuya
Published: March 2009

Functionally structured material is a tailored material to have unique geometric structures and create new functions or high performances. Design and fabrication of 3D ceramic photonic crystals and fractals using CAD/CAM stereolithography are demonstrated as well as their unique functions of reflection and localization of electromagnetic waves as typical examples of functionally structured materials. The outlook of functionally structured materials is briefly discussed.
Microstructure and Properties of WCP Reinforced Ferrous Gradient Composites
Authors: Song Yan Pei , Mao Xie Min , Dong Qi Ming , Tang Liu Ding , Ouyang Zhi Ying , Liang Hong Yu
Published: March 2009

Two kinds of thick-walled rings, consisted of WCP/Fe-C gradient composites layers containing
about 54 and 70 vol.% of WCP and Fe-C alloy core, were cast by centrifugal casting method. The microstructure,
mechanical properties and wear resistance of the gradient composites were investigated. Meanwhile
the results were compared with those made of the high speed steel. It was found that WCP in the two
kind of gradient composites layers were even well distributed, WCP/Fe-C composites layer of 23-28mm
was obtained, the transition layer between the composites layer and matrix alloy core was perfect. The
tensile strengths of the two gradient composites layers achieved 345MPa, 460MPa and the impact
toughness were 4.6J/cm2, 6.2J/cm2 respectively. Moreover the hardness of the composites layers attained
HRA81 and HRA 78. The result of the comparison among the gradient composites layers and that made of
the high speed steel showed that the wear resistance of the gradient composites layers containing about 50
and 70 vol.% of WCP was more than 20 times higher than that of the high speed steel under loads of 100N
and 200N and sliding velocity of 60 m/s. Finally, the wear-mechanism was discussed.
Microstructure and Corrosion Behaviour of Ni/Al-Al2O3 Gradient Ceramic Coatings on Q235 Steel
Authors: Fang Ming Hao , Liu Yan Gai , Huang Zhao Hui
Published: March 2009

Ni/Al-Al2O3 gradient ceramic coating was prepared on Q235 steel by plasma spraying.
Microstructure and corrosion behavior in boiling 5%HCl solution of the samples sprayed with this
coating were investigated. The results showed that thickness of Al2O3 ceramic coating was increased
greatly and almost no connected pores formed in the gradient coating due to the existent of Ni/Al-Al2O3
transition interlayer coatings. The corrosion resistance of Q235 steel with Ni/Al-Al2O3 gradient
composite ceramic coating in boiling 5%HCl solution was greatly improved.
Macro-Residual Stress in 304 Stainless Steel Coated with ZrO2-CeO2 Thin Films by Sol-Gel Process
Authors: Yu Xin Gang , Liu Lan Yun , Zuo Yan Bin , Wang Lin Jiang , Ma Hong Wen , Bi Wen Yue , Zhao Hui Feng , Wang Li , Long Fei , Luo Wu Wen
Published: March 2009

X-ray diffraction (XRD) method to measure the residual stress existing in the metal substrate
surface layer was introduced and the sol-gel ZrO2-CeO2 thin film was successfully prepared on SUS304
stainless steel substrate by dip-coating process. The macro residual stress existing in metal substrate was
analyzed by XRD. It turns out that the compressive stress existing in the metal substrate surface layer
increases with the increase of heat-treated temperature. Based on the above study, colored stainless steels
of high quality were prepared by sol-gel process.
Influence of Hydrothermal Conditions on ZST Powders for Microwave Ceramics
Authors: Bao D.Y. , Xiong Zhao Xian
Published: March 2009

(Zr0.8Sn0.2)TiO4 nanopowders for microwave ceramics were prepared by a hydrothermal synthesis
route. Effects of hydrothermal conditions on crystal structure, morphology and sintering performance
of the powders were characterized by X-ray, SEM and TG-DTA, respectively. The powders with
mean size of 80 ~ 200 nm was obtained. Ceramics with 92.3% of theoretical density were fabricated at
1260°C with the powders. Dielectric properties of the samples were measured and it gives a dielectric
constant of 35-36 and Q×f value of 4500-10000 GHz.
Structure and Electrical Properties of Pb(Ni1/3Nb2/3)O3-Pb(Zr/Ti)O3 Relaxors
Authors: Pan Jin Song , Zhang Xiao Wen
Published: March 2009

Ceramics with the type of 0.50Pb(Ni1/3Nb2/3)O3-0.15PbZrO3-0.35PbTiO3 were synthesized by
conventional mixed-oxide technique. The dielectric and ferroelectric properties of this composition were
investigated in detail. Frequency dispersion and diffuse phase transition were observed in the dielectric
behaviors. The revealed electrical properties are εm = 22388, Pr = 21.449 μC/cm2 and Ec = 5.191 kV/cm.
XRD experiments demonstrate that this composition is within the MPB region, which may help to explain
the super electrical properties discussed in this study.
A-Site Cational Size Disorder Effects in La0.55Ca0.45MnO3
Authors: Wang K.F. , Liu X.P. , Li Q.C. , Wang Y. , Wang L.F. , Dong S. , Yu H. , Liu J.M.
Published: March 2009

The effects of A-site cation size disorder in ABO3 type ferromagnetic metallic La0.55Ca0.45MnO3 system have been studied by substituting La3+ and Ca2+ by other ions, while keeping the valency of Mn ions and the A-site cation mean radius  constant in the substituted compounds with different A-site ionic radii variance σ2 = Σi (xiri 2 − 2), where xi and ri are the atomic fraction and ionic radii of i-type ions at A-site, respectively. It is revealed that the A-site disorder induces the decreasing of the magnetization and the increasing of the resistivity. The ferromagnetic Curie point TC decreases with the increasing of the A-site ionic radii variance, too. Moreover, the ground state of the system transits from ferromagnetic metal to glass insulator upon increasing variance of the A-site ionic radii from 0.0003 for La0.55Ca0.45MnO3 to 0.009 for Gd0.55Sr0.45MnO3. It is argued that the suppression of the ferromagnetism is ascribed to the enhanced radial distortion of the MnO6 octahedra due to the increasing A-site disorder.
Low Temperature Electrolyte for Li-Ion Batteries
Authors: He Xiang Ming , Pu Wei Hua , Han Jing Li , Yu Yan Mei , Jiang Chang Yin , Chen Jian , Wan Chun Rong
Published: March 2009

Electrolyte of LiPF6-ethylene carbonate (EC)-methyl acetate (MA) was prepared. 1 M
LiPF6-EC-MA electrolyte presented the conductivity in excess of 1 mS cm-1 at -50 oC. The cyclic
voltammetry showed that the electrolyte was better than conventional electrolyte of LiPF6-ethylene
carbonate (EC)-diethyl carbonate (DEC) for the formation of SEI film. 1 M LiPF6-EC-MA electrolyte
showed much better cycleability than conventional electrolyte of 1 M LiPF6-EC-DE·C for LiCoO2/Li cell.
It is a promising alternative electrolyte for Li-ion batteries.
Nano Sulfur Composite for Li/S Polymer Secondary Batteries
Authors: He Xiang Ming , Pu Wei Hua , Li Jian Jun , Jiang Chang Yin , Wan Chun Rong , Zhang Shi Chao
Published: March 2009

The Li/S polymer secondary batteries presents higher capacity, lower materials cost and much
better performance in higher operation temperature. A nano-scale sulfur polymer composite cathode
material has been developed for these batteries, and its cycle capacity is over 700mAh/g when the lithium
metal is used as the anode; A nano-scale Cu/Sn alloy powder has been synthesized by a novel
micro-emulsion process, its cycle capacity is over 300 mAh/g; The performance of PVdF gel electrolyte
has been improved through the addition of the nanometer SiO2 synthesized in-situ. The advanced Li/S
polymer secondary batteries will be a promising alternative for next generation energy storage system.
Up-Conversion Luminescence in Thulium Doped Barium Titanate Inverted Opal
Authors: Cao Jing , Zhou Ji , Li Bo , Fu Ming , Zong Rui Long
Published: March 2009

The synthesis, infiltration into a polystyrene opal and luminescence spectroscopy of BaTiO3:
Tm3+ were reported in this paper. A photonic band gap and blue up-conversion photoluminescence were
achieved in the synthesized inverted opal, respectively demonstrated by reflection spectrum and emission
spectrum excited by 650nm laser source at room temperature. Changes of the emission spectroscopy
compared with the thulium doped barium titanate reference sample were observed and thus provided
evidence for the light inhibition effect of the photonic structure.
Low Temperature Sintering (Ba1-xSrx)TiO3 Ceramics by Using CuO-TiO2 Mixture as Sintering Aid
Authors: Chan Chao Chin , Su Chean Cheng , Diao Chien Chen , Yang Cheng Fu
Published: March 2009

1wt% CuO-TiO2 (molar ratio, CuO/TiO2= 1) mixture is added as the liquid phase sintering aid to develop the sintering and dielectric characteristics of (Ba1-xSrx)TiO3 (x=0, 0.1, and 0.2) ceramics. The crystal characteristics of calcined (Ba1-xSrx)TiO3 powders and sintered (Ba1-xSrx)TiO3 ceramics are developed by using X-ray diffraction method. The calcined (Ba1-xSrx)TiO3 powders and 1050oC-sintered (Ba1-xSrx)TiO3 ceramics reveal a tetragonal or pseudo-cubic structure and the 1150oC-sintered(Ba1-xSrx)TiO3 ceramics reveal a tetragonal structure. Sintered at 1100oC, the (Ba1-xSrx)TiO3 ceramics present a porous structure; Sintered at 1150oC, the (Ba1-xSrx)TiO3 ceramics present a uniform growth. The grain size decreases with the increase of SrO content. In this study, the dielectric characteristics of CuO-TiO2 mixture-fluxed (Ba1-xSrx)TiO3 ceramics are also developed.
Microstructural and Micromorphological Studies on ZnSe Single Crystals Using AFM/FE-SEM/RO-XRD
Authors: Li Huan Yong , Jie Wan Qi , Wang Xiao Qin , Xu Ke Wei
Published: March 2009

The microstructure and surface micromorphology of ZnSe single crystals grown directly from
zinc and selenium have been investigated using rotation orientation x-ray diffraction (RO-XRD), atomic
force microscope (AFM) and field emission scanning electron microscope (FE-SEM). The ZnSe samples
exhibit only the surface leaning to (111) singular face by the angle of 3.13°, which is the buildup of
two-dimensional dendritic crystal layers. Numerous nuclei and cavities distribute unevenly across the
crystal surface, governing the formation of growth layer, while the dendritic crystal layers develop rapidly
by margining the smaller nuclei. The formation of these microstructure and micromorphology on the
surface of ZnSe crystals depends on the surface supersaturation and the growth parameters.
High Piezoelectric Property and Low Dielectric Constant PZN-PZT Ceramics
Authors: Zhou Dong Xiang , Deng Yi Hua , Gong Shu Ping , Yan Bo Wu , Zhuang Zhi Qiang , Han Ke
Published: March 2009

The influences of the substitution of (Zn1/3Nb2/3) group for Ti as well as addition of Fe2O3 and
K2CO3 on d33, kp, εr, and tgδ of the Pb[Zr0.46Ti0.54-x(Zn1/3Nb2/3)x]O3 + y mol%Fe2O3+z mol%K2CO3 (PZNPZT)
(0 ≤ x ≤ 0.20, 0 ≤ y ≤ 0.10, 0 ≤ z ≤ 0.20) ceramics were investigated. The experimental results
demonstrated that when x increases in Pb[Zr0.46Ti0.54-x(Zn1/3Nb2/3)x]O3+0.3 mol%Fe2O3+0.5mol%K2CO3
ceramics, the d33, kp, εr, and tgδ increase and approach to their maximum values, then eventually decrease.
XRD analysis revealed that the perovskite structure of the materials transfers from tetragonal phase to
rhombohedral phase. The relative dielectric constant (εr) decreases dramatically in the rhombohedral
phase area near the MPB; the d33 and εr decrease with the small amount of added Fe2O3 and K2CO3, which
also contributes to densification of the PZN-PZT ceramics. The optimized piezoelectric performances
through the experiment were obtained as d33=280 pC/N, kp=0.62, εr=900, tgδ=0.003.
Complex Impedance Spectroscopy of Bi-Substituted Yttrium Iron Garnet (YIG)
Authors: Zhao Hong Jie , Zhou Ji , Gui Zhi Lun , Li Long Tu
Published: March 2009

The effects of Bi-substitution on the complex impedance spectra of yttrium iron garnet (YIG) were studied in this paper. The polycrystalline yttrium iron garnet Y2BiFe5O12 (YIG: Bi) and Y3Fe5O12 (YIG) samples were prepared by solid-reaction method. The complex impedance spectra were measured in the frequency range from 1 KHz to 100MHz at several temperatures between 210oC and 500oC. The complex impedance sample shows that the YIG: Bi can be represented by double Cole-Cole semicircles, and the YIG can be represented by a single Cole semicircle. The physical structure of the specimen was visualized as comprising of small resistance grains separated by large resistance grain boundaries in accordance with the impedance spectra observations. The electrical processes in the sample were modeled in the form of an electrical equivalent circuit made up of a series combination of two parallel RC circuits attributed to grains and grain boundaries. The temperature dependence of bulk resistance indicated an evidence of Arrhenius-type thermally activated process, showing a close to linear variation up to a temperature of 740 K.
Effect of V2O5 Additive on the Microstructure and Electrical Properties of Mn-Co-NiO NTC Thermistor
Authors: Wang Wei Min , Liu Xiang Chun , Zhao Ming , Tian Chang Sheng
Published: March 2009

The aim of this paper is to investigate the effects of V2O5 additive on the electrical properties of
NTC thermistors based on Ni0.5Co0.5Mn2O4.The XRD analyses indicate that single spinel phase can form,
and V2+ions are in the octahedral interspace. The cell can be enlarged due to the V2O5 additive. The
resistivities (ρ) and the material constant (B) increase obviously, the reasons of which are mainly
attributed to the outer electron configuration of V2+ and cell enlargement.
Resistivity-Temperature Properties of La(TixMn1-x)O3 Ceramics
Authors: Ma Wei Bing , Hao Yan Xia , Qu Yuan Fang , Xu Ting Xian
Published: March 2009

Samples of La(TixMn1-x)O3 (0.1 ≤ x ≤ 0.7) were sintered at different temperatures. The
experimental results showed that the resistivity-temperature curves of the samples match NTC
characteristic. The crystal structure was analyzed using X-ray diffraction and the microstructure was
observed by scanning electron microscope.
Effect of Deposition Parameters on Crystallization of RF Magnetron Sputtered BST Thin Films
Authors: Zhang T.J. , Li S.Z. , Zhang B.S. , Huang W.H. , Pan R.K.
Published: March 2009

Ba0.65Sr0.35TiO3 (BST) thin films on p-silicon substrates were deposited by radio frequency
magnetron sputtering. The effects of the deposition parameters on the crystallization and
microstructure of BST thin films were investigated by X-ray diffraction and filed emission electron
microscopy, respectively. The crystallization behavior of these films was apparently affected by the
substrate temperature, annealing temperature and sputtering pressure. The improved crystallization
can be observed for BST thin films that deposited at higher temperature. The dominant X-ray
diffraction peaks became sharper and more intense as the annealing temperature increased. BST thin
films deposited at high sputtering pressure of 3.9 Pa exhibited the (110) + (200) preferred orientation.
Possible correlations of the crystallization with the sputtering pressure were discussed. The SEM
morphology indicated the film was small grains and smooth.
Dielectric Properties of Boron Nitride-Aluminium Nitride Composites Prepared by Spark Plasma Sintering
Authors: Chen Bin , Pan Wei
Published: March 2009

In this study, hexagonal Boron Nitride-Aluminium Nitride composites were prepared by spark plasma sintering at 1700°Cfor 4 min under the pressure of 25 MPa, varying the amount of BN from 0 to 30 wt.%. The dielectric constants and losses of the samples were measured from 100 Hz to 1 MHz at room temperature, and the results show that with the increment of BN content, the dielectric constants and losses of AlN-BN composites decrease. When the BN content is 20 wt.%, the dielectric constant and loss of the composites at 1 MHz are 6.18, 2.1 × 10-3 respectively.
Microstructure and Thermoelectric Properties of CoSb3 Synthesized by MA-SPS Method
Authors: Liu Wei Shu , Zhang Bo Ping , Li Jing Feng , Wang Heng
Published: March 2009

Single-phase polycrystalline CoSb3 skutterudite was prepared through a new combination of mechanical alloying (MA) and spark plasma sintering (SPS). In order to investigate the influence of MA conditions on the microstructure and thermoelectric properties, MA synthesis were carried out under various conditions with different milling times. The powder sample MAed for 6h still consisted of metal Sb, and then transformed to CoSb3 with a little amount of metal Sb and CoSb2 phases after MA for 15h. Further prolonging the MA time resulted in the decomposition of CoSb3 to CoSb2 phase. The average grain size of the SPSed samples decreased from 650nm to 250nm as MA-time was prolonged from 6 to 24h. Lattice parameters estimated form XRD patterns increase with the increasing MA time. All samples SPSed at 600°C for holding 5 min show an n-type conduction. The electrical resistivity was 1030, 895, 410, 260 μm for the samples from the MA-derived powders with MA-time of 6, 15, 24 and 33h at room temperature, respectively, then reduced to 60 μm at 400°C for all samples. An optimum MA time is 24 h in which the sample shows the highest power factor 612μW/m*K2 at 150°C.