bluuebunny/crossref_metadata_2025 huggingface dataset:
A Study of the Scallop Generation Mechanism in Ultra-Precision Raster Milling
Authors: Wang Su Juan , To Suet , Cheung Chi Fai , Lee Wing Bun
Published: March 2009

Ultra-precision raster milling (UPRM) can directly achieve the fabrication of threedimensional
non-axisymmetric freeform components with nanometeric surface finish and submicrometric
form accuracy. During the past few years, a lot of research on computerized numerical
control (CNC) machining technologies has been conducted; however, little of this research makes
any contribution to UPRM. This paper studies the mechanism of scallop height generation for
UPRM. Through analyzing the cutting edge locus and the scallop height generation mechanism, a
model for feed-intervals and for raster-interval scallop height generation, are presented. Parameters
such as selection of feed direction (vertical cutting and horizontal cutting), feed rate, spindle speed,
tool nose radius, swing distance, feed length and raster distance have been taken into consideration
in the scallop generation models.
A Framework of a Surface Generation Model in Fast Tool Servo (FTS) Machining of Optical Microstructures
Authors: Kwok Tsz Chun , Cheung Chi Fai , To Suet , Lee Wing Bun
Published: March 2009

In this paper, a framework of surface generation model in the fast tool servo (FTS)
machining of optical microstructures will be described. The integrated model is totally composed of
a tool path generator (TPG), a surface topography model (STM) and an optimization model (OM).
To develop the tool path generator, two parts should be involved. The first part is the tool path
generated based on cutting conditions such as the feed rate and spindle speed, the geometry of
optical microstructures, and diamond tool geometry. Another part is the synchronized motion
generated by the tool actuation of the FTS at a bandwidth higher than the rotational frequency of the
spindle. The surface topography model will be generated based on the TPG and used to predict the
technological aspects of FTS machining. It takes into the account the kinematic and dynamic
characteristics of the cutting process. The former includes the tool path generated by the tool path
generator. The later includes the relative vibration between the tool and the workpiece caused by the
axial error motion of the spindle as well as the synchronized motion of the FTS system. The
optimization model will be undertaken by an iterative algorithm, which will be developed based on
the TPG and STM. The OM will be expected to output the verified tool path, the suggested
optimum cutting conditions, and the diagrams with predicted cutting performance characteristic and
process parameters being investigated. Eventually, the successful development of this surface
generation model can contribute for the knowledge of ultra-precision machining with FTS and the
further development of the performance of the machining system.
Stiffness Analysis for a Novel Parallel-Robot Based High-Precision Flexible Assembly Fixture
Authors: Yu Hong Jian , Li Bing , Yang Xiao Jun , Hu Ying , Hu Hong
Published: March 2009

In this paper, a novel parallel mechanism (3-RRRS/UPR) used in flexible fixture with configuration composed of two parallel robots (2-RR and 3-RRRS/ UPR) is presented. First, system modeling including the mobility study is conducted. Then a novel methodology is proposed that makes use of screw theory to analyze the deformation and stiffness of the mechanism: firstly we identified the existence of the deformation of the subchain, in terms of the relationship between the effective screw and deformation screw; then we took the deformation as an infinitesimal motion of the mechanism, and the stiffness matrix corresponding to the deformation can be deduced. Finally the global stiffness matrix of the whole mechanism is modeled by assembling different stiffness characters based on the presented methodology.
Studies on Ni-Mo-P Coatings by Electroless Deposition
Authors: Chou Yu Hsien , Bai Ching Yuan , Ger Ming Der , Lee Shuo Jen , Lee Chi Yuan , Chao Chu Lung
Published: March 2009

This paper describes the performance of Ni-P and Ni-Mo-P alloy coatings deposited by
electroless plating on the aluminum alloy 5052 to evaluate the corrosion resistance, thermal stability
and electro-conductivity of coating assemblies. Corrosion behaviors of the obtained deposits in a
0.5M H2SO4 environment were investigated. The crystalline state and morphologies of Ni-P and Ni-
Mo-P alloys were examined by field emission scanning electron microscopy (FE-SEM). The
experimental results indicate that the Ni-Mo-P coating operated at 70°C and pH 9.0 has a
nanocrystalline structure and its corrosion resistance in a 0.5M H2SO4 environment can be enhanced
by the co-deposition of Mo as compared to Ni-P films. It has also been found that the Ni-Mo-P
ternary alloys reveal good thermal stability after annealing at 400°C. Based on the excellent
performance of Ni-Mo-P ternary alloys, these alloys have a potential to be applied to precision
mould, optical parts mould, and surface metallization of substrates.
A Novel Time Based Current Compensator for LED Back Light Modules
Authors: Fan Yi Hua , Wu Cheng Ju , Fan Chen Chao , Chih Kuo Wei , Liao Lun De
Published: March 2009

The paper proposes a novel time based brightness compensation circuit for LED back light modules. The brightness of LED decays while running under constant current driven condition. We have designed a suitable controller to compensate the driving currents to maintain the brightness. The compensation data were calculated from the relative luminous efficiency – time curve provided by the LED manufacturer and were stored in the microprocessor. -The embedded system used the running time of the LED in the back light module as an independent variable for tuning the driving current. The experiment results showed that the brightness of different operating times’ LED arrays can be held almost the same as the new ones.
The Study of Fabrication of the Liquid Core Waveguide Nutrient Sensor
Authors: Wu Chih Wei , Shen Yung Kang , Lee Yi Lung , Wei Chung Sheng , Hsiao Chun Ching
Published: March 2009

A novel nutrient sensor using liquid core waveguide technique is reported, implementing
Teflon AF 1601S coated microchannels. Straight PDMS microchannels replicated from a master
were coated with Teflon AF 1601S and sealed with a Teflon AF 1601S coated Pyrex 7740 wafer. It
formed a liquid core waveguide with a low index of refraction channel in which a high index
aqueous solution was flowed. Light generated by a fiber-coupled tungsten halogen lamp propagated
by total internal reflection to the end of the channel where the light was detected using a CCD array
spectrometer. There is a dramatic difference between channels with and without a Teflon coating.
The absorbance response of this sensor varies linearly with concentration. This innovative
technique provides a potentially low-cost and high efficient approach to fill the inspection
technology gap between in-situ and laboratory analyses. It is believed that the novel process is
expected to give an impact to the aqueous inspection and to create a highly value-added technology
in optical test, measurement industry.
Research and Simulation on the Wear Uniformity of Lapping Plate
Authors: Yuan Ju Long , Liu W.T. , Wang Zhi Wei , Wen Dong Hui , Zhou Zhao Zhong
Published: March 2009

Lapping plate wear is of great influence on shape precision of workpiece. Investigation
on the wear uniformity of uncertain eccentricity plane lapping was carried out in this research. The
relative velocity function of the plate to the workpiece is obtained through kinematic analyses in the
mode of uncertain eccentricity plane lapping, and material removal rate (MRR) function and wear
uniformity function were deduced based on Preston equation. Effects of the ratio and eccentricities
on the wear uniformity are discussed in detail through MATLAB simulation. Theoretical analysis
and simulation results show that the ratio k1 of workpiece revolution speed to lapping plate is the
key to decide whether the lapping plate is lapped uniformly. Theoretically, when k1<0, the greater
|k1| is, the better the lapped uniformly of lapping plate can be. The ratio k2 of workpiece rotation
speed to lapping plate has great influence on the lapped uniformly when k1 approximate 1, and k2
has little influence on the lapped uniformly when k1<0 or k1>1, Besides, a bit bigger eccentricity e1
is propitious to the lapping uniformly of the lapping plate, and bigger eccentricity e2 are also helpful
to lapping uniformly of the lapping plate. And the conclusion could be extended to single-side plane
lapping and double-side plane lapping process.
Study on Micro-Feature of Backlight Module for Micro Injection Molding Technology
Authors: Shen Yung Kang , Lin Yi , Lee Jeou Long , Liu Fwu Hsing , Wu Chih Wei , Ou Keng Liang , Wu Wei Yu , Tu Ya Chan
Published: March 2009

This research first indicates the melt front delay of wedge-shaped lightguiding plate of
backlight module on micro injection molding. This research fabricated the patterns of mold insert of
lightguiding plate by photo etching process. The micro-facture of lightguiding plate was
manufactured by micro injection molding. The lightguiding plate of backlight module was used for
the PMMA material. The single parameter method was used to discuss the flatness and replication
properties for different processing parameters (mold temperature, melt temperature, packing
pressure, packing time and injection pressure). The results show that there are melt front delays due
to the slow injection velocity, the low temperature induced by the little effect of shear heating, the
high viscosity, the large flow resistance and the slow flow velocity. The mold temperature is the
most important factor for the flatness and the replication of micro-feature of liughtguiding plate.
Lower mold temperature induces better flatness properties. The surface roughness of micro-facture
of lightguiding plate is 8.8 nm on micro injection molding for this work.
An Experimental Study of the Formation of Tool Marks Made by Facet Diamond Cutting Tools in Single-Point Diamond Turning
Authors: Kong Ming Chu , Lee Wing Bun , Cheung Chi Fai , To Suet
Published: March 2009

The formation of tool marks in single-point diamond turning is a fundamental study of
the effect of materials swelling and recovery on surface roughness on a machined surface. A series
of orthogonal face cutting tests has been conducted among plate aluminum alloy, oxygen-free high
conductivity copper and electroless nickel phosphorus under the same cutting conditions by the use
of facet tools with different front clearance angles. The results show that the regular width of the
undulating pattern in tool marks could be explained by side swelling and the micro-waviness within
a tool mark is caused by burnishing and recovery.
The Study of Precision Hard Turning of the Hardened Mold Steel
Authors: Lin Wei Shin
Published: March 2009

Hard turning has the advantage of rapidly, elasticity and low energy consuming. It has
been a trend to replace the complex grinding processes, especially for small batch machining.The
surface roughness value of steel after being grinded will ranged in 0.1 to 1.6 μm Ra. This paper
points to the precision hard turning of the hardened mold steel, seeking the cutting conditions that
can be received in the surface roughness value below 0.1μm Ra, in order to replace the grinding
processes.
The precision dry turning test were conducted with ceramic cutting tools. The nose radius of the
cutting tool was 1.2 mm and the depth of cut was fixed at 0.05 mm. Through a series of turning test,
it can be found that, when cutting speed was at 80 to 200 m / min, and feed rate at 0.005 to 0.009
mm / rev, the surface roughness value would be all below 0.1μm Ra. It was superior to grinding
process. So we can say that, it is possible to replace the grinding process by hard turning when
machining the hardened mold steel.
Prediction of Surface Roughness in High Speed Milling Process Using the Artificial Neural Networks
Authors: Kim Dong Woo , Shin Young Jae , Park Kyoung Taik , Lee Eung Sug , Lee Jong Hyun , Cho Myeong Woo
Published: March 2009

The objective of this research was to apply the artificial neural network algorithm to
predict the surface roughness in high speed milling operation. Tool length, feed rate, spindle speed,
cutting path interval and run-out were used as five input neurons; and artificial neural networks
model based on back-propagation algorithm was developed to predict the output neuron-surface
roughness. A series of experiments was performed, and the results were estimated. The
experimental results showed that the applied artificial neural network surface roughness prediction
gave good accuracy in predicting the surface roughness under a variety of combinations of cutting
conditions.
Optimization of Free-Form Illumination Optics
Authors: Kataja Kari , Aikio Mika , Niemelä Karri , Aikio Mauri
Published: March 2009

We have developed optimization methods for generating free-form surfaces. The main
applications are in the industrial on-line spectroscopic and machine visions measurements, where
spectral and spatial uniformity, good efficiency and pass-line stability are required parameters. We
used commercial software for ray-tracing engine. We have developed in-house optimization
routines, but used also build-in functions. In this work we have designed a speckle free alternative
for laser line generation based on the LED sources. The optical system is based on the collimation
part and a free-form mirror. Simulation results are presented.
Monitoring of Temperature Distribution within a Silicon-Based Micro Reformer Using Array Micro Sensors
Authors: Lee Chi Yuan , Lee Shuo Jen , Dai Ching Liang , Wu Chin Hua , Wu Guan Wei
Published: March 2009

With advances in micro fuel cell development, the production of hydrogen for micro
reformer has become increasingly important. However, some problems regarding the micro
reformer are yet to be resolved. These include reducing the size, reducing the quantity of CO and
combining the fuel cell, among others. Accordingly, in this investigation, array micro temperature
sensors and heaters were combined within a silicon-based micro reformer to measure and control
the temperature and thus improve performance and minimize the concentration of CO.
In this work, micro-electro-mechanical-systems (MEMS) of the micro channel type were
fabricated on a silicon substrate to enhance the methanol conversion ratio. Array micro temperature
sensors and heaters were made of platinum and placed inside the micro reformer. Although the
micro temperature sensor and heater have already been used to measure and control temperature in
numerous fields, they have not been employed in micro reformer and commercial products.
Therefore, this study presents a new approach for combining array micro temperature sensors and
heaters within a silicon-based micro reformer to minimize the size and improve performance.
Solid Deformable Multibody Dynamic Problems in Precision Manufacturing Systems
Authors: Hwang Yunn Lin
Published: March 2009

The recursive projection schemes used in most existing recursive methods for solid
deformable structure dynamic problems in precision manufacturing systems lead to dense
coefficient matrices in the acceleration equations and consequently there is a strong dynamic
coupling between the joint and elastic coordinates. When the number of elastic degrees of freedom
in engineering materials increases, the size of the coefficient matrix in the acceleration equations
becomes large and consequently the use of these recursive methods for solving the joint and elastic
accelerations becomes less efficient. This paper discusses the problems associated with the recursive
projection schemes used in the existing recursive methods, and it is shown that decoupling the joint
and elastic accelerations using the nonlinear recursive method requires the factorization of nonlinear
matrices whose dimensions are independent of the number of elastic degrees of freedom of the
multibody system. An amalgamated formulation that can be used to decouple the elastic and joint
accelerations for different multibody manufacturing systems is then proposed. The use of the
nonlinear recursive method developed in this paper is demonstrated using the open-loop and closedloop
chains in precision manufacturing systems.
Thermal Transpiration of Liquid in Nanoscale Channel: A Molecular Dynamics Simulation Study
Authors: Han Min Sub
Published: March 2009

The liquid flow in nanoscale channel under thermal gradient, or so-called thermal
transpiration, is studied by Molecular Dynamics Simulation. The phenomenon was realized in two
fluid systems which differed from each other in the methods for applying the temperature gradient.
One used heat source and the other wall-heating. The channel was periodic and its walls consisted
of two different materials: conducting, high energy wall and non-conducting slip wall. It is shown
that the liquid in a periodic channel can effectively be driven by the thermal transpiration. Various
characteristics of the flow are discussed that include the temperature gradient, velocity profile and
liquid structure in the channel.
Research on Surface Microstructures of Nanocomposite Ceramics in Two-Dimensional Ultrasonic Ultraprecision Grinding
Authors: Zhao Bo , Tong Jing Lin , Wu Yan , Gao Guo Fu
Published: March 2009

Using TEM, SEM and XRD, the surface microstructures of nanocomposite ceramics
prepared by heterocoagulation was studied in two-dimensional ultraprecision grinding with
ultrasonic assistance. This research was focused on the structure of ground surface degenerating
layer, surface generation mechanism and characteristics of nanocomposite ceramic parts. The
experimental results showed that the microscopic deformation mechanism of the ordinary Al2O3
parts was grain- boundary twinning and grain-boundary sliding while microscopic deformation
mechanism of nanophase ceramic parts was the inner crystal dislocation of strengthened phase with
intragranular structure. And its deformation coordination mechanisms were the grain-boundary
sliding and coordination deformation of intercrystalline second-phase.
The observation on the fracture surfaces of nanocomposite materials with different microscopic
structures by TEM and SEM showed that ZrO2 particles had an important effect on the generation
and expansion of crack in ceramic parts. The introduction of ZrO2 particles strengthened the
interface intensity of grain boundary. If there were rich ZrO2 particles on the grain boundary, the
cracks generated during the grinding process would be prevented. Smooth and plastic deformation
processing surface was obtained. It was proved further that the nanophase materials behaved
transcrystalline fracture due to the nano particles, dispersed in the grain boundary and prevented the
expansion of crack. This material’s fracture behavior made favorable surface possible. In the
precise grinding of nano materials, the plastic removal mechanism dominated the process. The
dislocated depth of the nanocomposite ceramics after grinding was bigger than that of common
ceramics, which meant that dislocation increased.
Photocatalytic and UV Characterization of TiO2 Nanofluid Prepared by SANSS on HVAC
Authors: Jwo Ching Song , Chen Chien Chih , Chang Ho , Chen Sih Li , Ho Shin Jr
Published: March 2009

This study develops a measurement method for testing the efficiency of photocatalysts in
the degradation of NH3 gaseous concentrations. The catalysts used in this study are the same as
those used previously in our UV/VIS spectrophotometer. Reaction measurements were carried out
at 27°C and 17°C under ambient pressure on Heat Ventilating and Air Conditioning (HVAC)
system. Quartz plates were coated with TiO2 nanocatalyst. Then the plate was put in the stable
reaction cell under different flow rates of circulation. The experiment gives a direct and simple
measurement of ammonia flux and hence of overall ammonia emission rate. The results reveal that
the Submerged Arc Nanoparticle Synthesis System (SANSS) TiO2 nanocatalyst has excellent
degradation efficiency towards NH3, so that when it is exposed to UV irradiation for 60 minutes, the
gaseous concentration can be reduced to 10% of the original concentration. In addition, the rate
constant of the degradation reaction of the self-made TiO2 nanocatalyst towards NH3 is as high as
0.039min-1.
Study of Ultrasonic Field in Polishing Based on Coupling Vibrations of Liquid
Authors: Huang X.Z. , Guo Zhong Ning , Huang Zhi Gang , Li Q.H. , Yu Z.Q. , Yue T.M. , Lee Wing Bun
Published: March 2009

The influences of ultrasonic field to polishing performance of Polishing Based on
Coupling Vibration of Liquid (PCVL) are analyzed here. The simulation results shows that sound
field in the original polishing device is rather uneven due to the existence of standing wave. To
obtain better polishing performance, the experimental equipment was modified. Uniformity of the
sound field was improved by preventing standing wave, thus a better surface quality could be
achieved. Furthermore, a higher machining efficiency could be also obtained because sound
intensity was strengthened at the same time. From the results serials of experiments, the
improvements made by modified equipment are clearly shown.
Influence of Process Parameters on T-Shape Tube HydroForming Characteristics for Magnesium Alloy
Authors: Lin Shen Yung , Chang C.M. , Chang C.K.
Published: March 2009

Due to the light weight and electromagnetic interference shielding capabilities in magnesium alloy material, it is widely utilized in 3C electronic components and automobile parts. However, its formability is very poor due to the phenomenon of negative strain hardening rate appearing as the deformation in large strain range, so it is usually formed as die casting or casting styles leads to much scrap, and manufacturing cost is thus increased. The objective of this study is to investigate the effect of process parameters on T-shape tube hydro-forming characteristics for magnesium alloy and it may offer the data resulting from the analysis to predict an acceptable product of tube fitting for magnesium alloy forming in industry. AZ31 magnesium alloy tube is used as the billet material for hydro-forming with hydraulic pressure as the main forming power combined with the mechanical auxiliary force from the punch to fabricate the T-shape tubing products. Finite element code DEFORM-3D is adopted to investigate the forming states of T-shape tube forming, by changing process parameters; such as punch velocity, hydraulic pressure, fillet radius of the die and tool-workpiece interface friction etc. to investigate the material flow of tube fitting, wall thickness variations, and stress and strain distributions. By qualifying the forming processes whether if it is completed or not, and synthesizing the overall analysis and judgment, we establish an admissible level of process parameter range for complete tube manufacture. The results show that suitable mechanical force can help material flow, prevent large strain deformation falling into the area of negative strain hardening rate, enhance magnesium alloy to become easy in forming and make tube fitting to be formed successfully.
An Empirical Approach for Identification of Sources of Machining Errors in Ultra-Precision Raster Milling
Authors: To Suet , Wang Hao , Li Bing , Cheung Chi Fai
Published: March 2009

Ultra-precision raster milling is one of the most significant techniques for the fabrication
of high precision components with the surface roughness less than 10nm and form errors less than
0.2 um, without the need for any subsequent polishing. However, no matter how well a machine
may be designed, there is a limit to the accuracy that can be achieved. This paper studies the
machining errors caused by the diamond tool and the axis motions using Freeform 705G. With an
empirical approach, the error sources are separated based on their effects on the surface finish. The
main source leading to poor surface finish is identified. This establishes a basis for subsequent error
compensation and equipment maintenance.
Input Parameters Determination for Predicting Ram Speed and Billet Temperature for the First Billet
Authors: Sabater Marc , García-Romeu Maria Luisa , de Ciurana Joaquim
Published: March 2009

The aim of this paper is to present the results of the first step of a defined methodology for the neural network tool development. That first step is to studying the variables that have influence on extrusion process, especially in those that affect billet temperature and extrusion speed. In order to determine those parameters, a preliminary analysis was conducted with experimental data from real industry. Then, a multiple regression analysis was carried out to define which parameters will be the inputs of the neural network prediction tool.
Ferroelectric Properties of Sol-Gel Derived Ca1-xSrxBi4Ti4O15 Thin Films
Authors: Fan Su Hua , Xu Jing , Hu Guang Da , He Bo , Zhang Feng Qing
Published: March 2009

Ca1-xSrxBi4Ti4O15 thin films were fabricated by sol-gel method on Pt(100)/Ti/SiO2/Si substrates. Influence of Sr content on the microstructure and ferroelectric properties of Ca1-xSrxBi4Ti4O15 thin films were systematically studied. The results indicate that Ca0.4Sr0.6Bi4Ti4O15 thin film has better ferroelectric properties with remanent polarization (2Pr) of 29.1+C/cm2, coercive field (2Ec) of 220 kV/cm. Furthermore, the film has good fatigue resistance. The better ferroelectric properties of Ca0.4Sr0.6Bi4Ti4O15 thin film originate from the relatively high concentration of a-axis oriented grains.
Wear Properties of Basalt Fibers Reinforced Composites
Authors: Xin Shao Bo , Liang Xiao Ping , Liu Hua Wu , Zhong Zhi Li
Published: March 2009

Compared to traditional fiberglass, basalt fibers have a wide spectrum of applications used as
textile fiber or reinforcement for composites. Epoxy resin composites filled with basalt fibers were
prepared by proper curing, using KH-550 silane coupling agent to enhance the interfacial bonding
between the inorganic reinforcing agent and the polymer matrix. The milling abrasive wear was investigated
in slurry containing sand abrasive particles using milling equipment. The experimental results
indicated that basalt fibers, EP and the nano-sized SiO2 filling formed steady composites. The wear rate of
the sample was reduced with the increase of resin content before the content of resin amounted to 40%.
When the content of resin is more than 40%, the wear rate of the sample deceased slightly.
Heat Storage Performance of a PCM Heat Exchanger with Calcium Chloride Hexahydrate
Authors: Zhu Xiao Qin , Hu Jin , Lu Jian Sheng , Sun Jia Lin , Yang Yu Fen , Ben-Abdallah N.
Published: March 2009

Calcium chloride hexahydrate (CaCl2·6H2O) is an important inorganic phase change material used for heat storage at lower storage temperature. Heat storage in a PCM heat exchanger is an effective means of energy conservation or recovery in many engineering applications. A study was made on heat storage performance of a PCM heat exchanger with staggered tube bank in which there are full of calcium chloride hexahydrate solution. The experimental measurements of its heat storage and discharging performances during the heating/cooling cycle were carried out at a given rate of air flow. The analyses and discussion of its experimental results were also made. Its prospect in the industrial applications as heat energy storage was forecasted.
Degassing Behavior and Solid State Reaction of Nano-Ti(CN) Base Cermets in Sintering
Authors: Zhou Shu Zhu , Qin Ye Xia , Wan Chun Lei , Liu Kai Qi , Qi Long Hao , Pan Wei
Published: March 2009

The chemical composition and solid state reaction of the nano-Ti(CN) base cermets in different
sintering temperature were studied. The total carbon and oxygen content in compact were declined
gradually with the increasing of sintering temperature, the nitrogen content in compact began to decline
above 1100°C, the peak of de-gassing of N2 was formed before the emergence of liquid phase, the
decomposition of N2 was arisen acutely above 1500°C. Mo2C and TaC diffused and took part in solid
state reaction with Ti(CN) above 900°C, the solid state reaction was finished below 1200°C. WC diffused
and took part in solid state reaction with Ti(CN) above 1100°C, it was dissolved below 1250°C, there
were only two phases, Ti(CN) and Ni(Ni+Co), in the alloy.
Synthesis of Aluminum Nitride by Nitridation of γ-Al2O3 Nanoparticles in Flowing Ammonia
Authors: Huang Zong Hao , Qi Long Hao , Pan Wei , Miao He Zhuo
Published: March 2009

Aluminum nitride (AlN) powder was synthesized by gas reduction–nitridation of γ-Al2O3,
using NH3 as the reactant gas. The results showed that AlN can be fabricated by this process at 1100°C for
over 480 min in the flowing NH3 atmosphere. However, no AlN was found in the products synthesized at
1300°C and 1400°C, which was different from the former reports. A series of experiments with different
parameters were carried out, and the effects of reacting temperature and time on the synthesis of AlN were
investigated. The reaction mechanism was also studied.
Reconstruction of Cranial Bone Defects Using a Compound of Bone Marrow Stromal Cells and Hydroxyapatite-Tricalcium Phosphate
Authors: Liu Lei , Chen Run Liang , Lin Yun Feng , Tian Wei Dong , Li Sheng Wei
Published: March 2009

Hydroxyapatite-tricalcium phosphate (HA-TCP) is a new kind of material which shows good biocompatibility, biological degradability, and porosity. This study aimed to determine the effectiveness of HA-TCP as a bone tissue engineering scaffold. In this study, critical size cranial defects were reconstructed with compounds of autogenous bone marrow stromal cells (BMSCs) and HA-TCP. The resulting grafts were examined by X-ray, histological examination, semi-quantitative analysis of osteogenesis, immunochemical examination (collagen type I and III), scanning electron microscopy and transmission electron microscopy. The results showed that HA-TCP is a good bone tissue engineering scaffold and BMSCs/HA-TCP is a promising technique for reconstruction of bone defects.
Preparation and Properties of CaCu3Ti4O12 Thick Film by Aerosol Deposition Method
Authors: Ma Ji Feng , Lin Yuan Hua , Nan Ce Wen , Tsurumi Takaaki
Published: March 2009

CaCu3Ti4O12 (CCTO) ceramic thick films have been prepared on Copper substrate, using ceramic powders by an aerosol deposition method (ADM). The ceramic powders are prepared by traditional solid state reaction processing at 1100 oC for 5 h. X-ray diffraction and scanning electron microscopy are used to investigate the microstructure and the phase composition of the deposited films. The results indicate that thick films are pure CCTO phase and homogenous. The dielectric impedance spectra indicate that the dielectric constant of CCTO thick film can reach 3×103.
XPS Studies on ZrO2 Thin Films Deposited on Glass Substrate by Sol-Gel
Authors: Yu Xin Gang , Gong Yi , Bi Wen Yue , Tian Xue Chun , Ma Hong Wen , Zhao Hui Feng , Qiu Guo Hong , Wang Li
Published: March 2009

The chemical composition and the valence state of elements on the surface of ZrO2 thin films
deposited on glass substrates have been studied by X-ray photoelectron spectroscopy. Results show that:
elements of Na, Mg, Zr, Ca exist in the form of their respective stable state, such as Na2O, MgO, ZrO2,
CaO, when heat treated at 500°C for 0.5h; but Si is unstable, and exhibit stoichiometrical disturbances.
Results of chemical composition and their content by atom percent of ZrO2 thin films surface reveal that:
Si, and Ca diffuse from glass to the thin films in scale; Na diffuses few and Mg collects to the thin films
surface. The diffusion of Mg2+ and Ca2+ from glass to ZrO2 thin films is negative diffusion.
Preparation of Molybdate Conversion Coatings on the Anodizing Surface of Aluminum Alloy
Authors: Du Shi Guo , Yan Jun , Cui Hai Ping , Wang Bin
Published: March 2009

Molybdate conversion coatings were prepared on the anodized surfaces of aluminum alloy
substrates, and the corrosion resistance in 3.5% NaCl solution was also investigated. The effects of the
main parameters on the quality of the coatings were discussed. The morphology and chemical
composition of the conversion coatings was examined by SEM and EDS. SEM observation showed that
the coatings were composed of small sheet grains with tiny cracks between them. EDS analysis showed
that the main element of the coatings was molybdenum. The results of polarization curve showed that the
coatings effectively inhabited the pitting corrosion of aluminum alloy substrates. In the end the possible
conversion mechanism was discussed.
Fabrication and Characterization of Ceramic/Metal Composite Wear Preventive Coating
Authors: Xiao Jin Sheng , Qin Feng , Zhao Wen Hua , Fu Wei Biao
Published: March 2009

The air plasma spray (APS) technology was used to prepare WC/NiCrAl and WC/NiCrBSi
ceramic/metal composite wear preventive coating on cast iron substrate. The microstructure,
microhardness, bond strength and slurry wear preventive performance of coating was measured. The
results revealed that all of the coating prepared by APS has good qualities. The coating with NiCrBSi as
its combining metal is better than that with NiCrAl on wear preventive performance, and coating
containing more WC is supreme than that containing less WC. Finally, wear mechanics and the principle
of the coating’s wear preventive property was concluded.
Preparation and Thermophysical Properties of (La0.4Sm0.5Yb0.1)2(Zr0.7Ce0.3)2O7 Ceramic for Thermal Barrier Coatings
Authors: Liu Ling , Xu Qiang , Wang Fu Chi , Zhang Hong Song
Published: March 2009

A complex rare-earth zirconate (La0.4Sm0.5Yb0.1)2(Zr0.7Ce0.3)2O7 powder for thermal barrier
coatings (TBCs) was synthesized by coprecipitation method. The phase composition, microstructure and
the thermophysical properties were investigated. XRD results revealed that single phase
(La0.4Sm0.5Yb0.1)2(Zr0.7Ce0.3)2O7 with pyrochlore structure was prepared and the SEM result showed that
the microstructure of the product was dense and no other phases existed among the particles. With the
temperature increasing, the thermal expansion coefficient (CTE) of the ceramic increased, while the
thermal conductivity decreased. The results indicated that CTE of the ceramic was slightly higher than
that of La2Zr2O7 and the thermal conductivity of the ceramic was lower than that of La2Zr2O7. These
results imply that (La0.4Sm0.5Yb0.1)2(Zr0.7Ce0.3)2O7 can be explored as the candidate material for the
ceramic layer in TBCs system.
In Situ Formation of NbC Reinforced Ni3Si Intermetallic Compounds by Laser Cladding
Authors: Sun Yao Ning , Fan Ding , Zheng Yu Feng , Zheng Min , Zhang Jian Bin
Published: March 2009

Laser cladding technique was used to form Ni3Si intermetallic composite coating reinforced by
in-situ formation NbC particles on Ni-based superalloy substrate. The process parameters were optimized
to obtain cladding. The effect of Nb-C addition to the microstructure of the coating was investigated. The
morphology of reinforcement particles was discussed. 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 good and free from cracks and pores. The microstructure of the coating was mainly
composed of Ni(Si), Ni3(Si, Nb) and NbC. The NbC particles were formed by in-situ reaction between Nb
and C during laser cladding process. NbC particles were homogeneously distributed in the composite
material. Moreover, the maximum size of NbC particles was more than 4 μm.
On the Microstructure of Aluminum Titanate Powders Coated with Mullite Sol
Authors: Zhou Jian Er , Hu Xue Bing , Li Hui Li , Wang Yan Xiang , Wang Yong Qing , Zhang Xiao Zhen
Published: March 2009

The mullite sol was prepared using tetraethyoxysilane (TEOS) as raw materials. Aluminum
titanate (AT) powders were coated with the sol by dipping. The influence of the concentration of the
mullite sol and pH value on the microstructure of the coated AT powders was studied. The results showed
that AT powders are coated homogeneously and the thickness of the mullite film is about 0.15 μm when
the concentration of the mullite sol is 0.18 mol·L-1 and pH value is 3.0.
Microstructure and Properties of Calcium Borosilicate and Borosilicate Glass-Ceramic Composites
Authors: Lu An Guo , Qiu Tai
Published: March 2009

Calcium borosilicate (CaO-B2O3-SiO2, CBS) glass based glass-ceramic composites were
prepared by introducing borosilicate glass. The effects of borosilicate glass and firing temperature on the
microstructure and properties of the glass-ceramic composites were investigated. The results showed that
the composites containing 0~40% (in mass fraction, the same below) borosilicate glass can be sintered at
850°C. The dielectric constant (εr) decreases with the increase of borosilicate glass content and can be
adjusted in the range of 5.6~6.6. The coefficient of thermal expansion (CTE) increases with the increase
of borosilicate glass content. Increasing sintering temperature favors the precipitations of crystal phases,
which have lower εr than CBS glass, resulting in the decrease of εr for the composites.
Preparation and Characterization of the Sol-Gel Derived Bioactive Glass-Fibers
Authors: Chen Xiao Feng , Li Yu Li , Zhao Na Ru , Chen Hao
Published: March 2009

The sol-gel derived bioactive glass short fibers in the system CaO-P2O5-SiO2 was prepared
using air-spray method. SBF immersion test indicated that the fibers possessed satisfactory bioactivity.
SEM, XRD, FTIR analysis revealed that the morphologies and bioactivity of the fibers could be
significantly influenced by the composition and viscosity of the solution. The fibers are very promising
biomaterials for applications to bone restoration and tissue engineering as the bone defects fillers or
additives for strengthening of the biomedical polymers.
Preparation of Layered Potassium Titanate
Authors: Yan Lu Ting , Si Wen Jie , Teng Feng , Zheng Yan Peng , Dai Chun Ai
Published: March 2009

Layered potassium titanate is an important intermediate in preparing titania nanosheets. Three
methods including method of potassium stearate, method of stearic acid and method of high-temperature
solid-state reaction were used to produce layered potassium titanate in this paper. XRD and SEM were
used to characterize the crystal structure and shape. The result of experiments showed that method of
potassium stearate was the most effective way to prepare the layered potassium titanate.
Preparation of Titania Film by Vapor Decomposition of Chelated Tetrabutyl Titanate
Authors: Xie Bing , Zhang Shao Hua , Hu Bing Feng , Luo Lai Tao
Published: March 2009

The vapor decomposition of chelated tetrabutyl titanate on glass substrate was used for the
preparation of titania films. The influences of decomposition temperature, chelant concentration on the
photocatalytic properties of titania film were investigated. The films were characterized by XRD, ATR
and the precursor solution was characterized by DTA.
XPS Investigation on Nano-TiO2 Modified by Titanate Coupling Agent
Authors: Zhang Dong Mei , Yang Hai Li , Yu Shou Wu , Sang Xiao Ming
Published: March 2009

Nano-TiO2 was modified with a titanate coupling agent, LICA38 [neopentyl (dially) oxy, tri
(-dioctyl) pyrophosphate titanate]. X-ray photoelectron spectroscopy (XPS) was used to evaluate the
surface characteristics of the bare and the modified nano-TiO2. It was demonstrated that the carbon
content of the bare TiO2 is 37.9 atm. %, and that of the modified TiO2 is 47.2 atm. %. Moreover, the
density of the -C-H (-C-C) and -C-O groups increases due to modification, and the atomic percentage of
C=O and -OH groups reduces. These results indicate that the -C-H (-C-C) and -C-O groups from LICA38
have been introduced to the surface of nano-TiO2 by coupling reaction with the hydroxyl groups.
Preparation and Bactericidal Properties of Nano-SiO2 Grafted with Macromolecular Quaternary Ammonium Salts Derivative of Alkylated Polyethylenimines
Authors: Wu Yuan Gen , Tong Hui , Qiu Shu Yi , Wang Xiao
Published: March 2009

Water-soluble polyethylenimine (PEI) was grafted onto the surface of nano-SiO2 particles
through the intermedium effect of 4-bromobutyryl chloride, and the water-insoluble SiO2 containing
macromolecular quaternary ammonium salts (MQAS/SiO2) was prepared followed by the
N-alkylation of coated PEI with 1-bromohexane and idomethane. The results of FT-IR analysis
testified that PEI is successfully immobilized on the surface of SiO2 nanoparticles. The minimum
inhibitory concentrations of MQAS/SiO2 against Gram-positive bacterium, Staphylococcus aureus,
and Gram-negative bacterium, Escherichia coli, are 100ug/ml and 1200ug/ml, respectively. The
bactericidal efficiency of exhaustively washed MQAS/SiO2 did not decline significantly compared to
the MQAS/SiO2without washing.
Preparation of Wear-Resistant Ceramics with Tangshan Ironstone-Tailings
Authors: Wu Xiao Xian , Huang Jun Tong , Huang Zhao Hui , Liu Yan Gai , Fang Ming Hao
Published: March 2009

Wear-resistant ceramics were prepared successfully with Tangshan Ironstone-tailings. The
effects of additives and sintering temperature on their mechanical property were studied. The erosive
wear performance of ceramics was evaluated in liquid-solid flow. The erosive wear mechanism was also
analyzed. The results showed that the wear-resistant ceramic prepared at 1200°C using 50wt% Tangshan
Ironstone-tailings 10wt%, mild-clay and 40wt% high aluminum fly ash as the starting materials had high
strength and good erosive wear resistance. The erosive wear mechanisms were washout particles’
micro-cutting and liquid washing.
Microwave Dielectric Ceramics and Devices for Wireless Technologies
Authors: Xiong Zhao Xian , Xue X. , Qiu Hong , Zhang C. , Fang C. , Luo J. , Bao D.Y. , Liu W. , Xiao F. , Lin Chang Jian , You B.Q. , Yue Zhen Xing
Published: March 2009

In this paper, several kinds of synthesis techniques were adopted; not only conventional solidstate reaction method but also solution synthesis techniques, including co-precipitation and hydrothermal synthesis, in addition to the gel-casting for complex shape of ceramic components and tape-casting of large scale thin plate for microwave IC. Different kinds of microwave ceramics were prepared, such as materials with low permittivity and high quality factor, moderate permittivity and good quality factor, and, high permittivity and reasonable quality factor, in addition to near zero of temperature coefficient of resonance frequency. Series of microwave devices were developed, for examples, dielectric resonators, dielectric filters, GPS antennas, communication connectors, and thin substrates for microwave IC.
Reaction Processes and Thermodynamic Modeling for SiAlON Structural Ceramic Powders Synthesized from Nonmetallic Mine
Authors: Xu Li Hua , Zhang Xiao Meng , Lian Fang , Di Yun Ping , Wang Huan , Liu Ming , Wang Ti Zhuang , Li Wen Chao
Published: March 2009

SiAlON family matrix materials have been fabricated from nonmetallic mine. The process of
Carbothermal Reduction and Nitridation (CRN) is selected on the basis of raw rocks containing various
Si/Al ratios. Thermodynamic analysis of Si-Al-O-N system at different sintering temperatures indicates
once the temperature is above 1673 K, a series of chemical reactions occur in sequence, SiO2, SiO,
Si2N2O, SiO2+Al2O3, mullite, X-SiAlON, O′-SiAlON, β-SiAlON, SiAlON- polytypiods and Si3N4+AlN.
Moreover, most of the reactions are exothermal and are promoted by further heating. The adding or in-situ
formed SiC can reduce mullite and Al2O3 to produce O′- or β-SiAlON, and its reaction is surprisingly
endothermic and is inhibited when further heated. Also, atmosphere is essential to affect the sintering
process. Either raising N2 partial pressures or reducing CO partial pressures can accelerate CRN progress.
Correspondingly, phase content and microstructure of the product converted from nonmetallic ore are in
detail investigated via X-ray diffraction (XRD) and scanning electron microscopy (SEM).
Formation of Mg2Si - 10vol%Al Composite via Solid-State Reaction
Authors: Zhou Qi , Zang Shu Jun , Ma Qin , Liu Jian Jun , Chang Chun Lei
Published: March 2009

Mechanical milling effects on the formation of Mg2Si-based composite toughened by Al in-situ
via solid-state reaction were investigated. The results indicated that, during annealing, the growth of
nano-Mg2Si grain has two obvious stages, the slow growth stage at low temperature (190°C < T < 400°C)
and the rapid growth stage at high temperature (400°C <T<600°C). With the increase of annealing
temperature, the ratio of the formation of Mg2Si increases and the microstrain decreases. Mechanical
milling could promote the formation of Mg2Si and lower the formation temperature. The reaction
temperature of powders milled for 50 h decreased nearly 350°C than that of the unmilled powders.
Joining ZrO2 to Al2O3 Ceramics Using Al2O3-ZrO2-SiC Slurries
Authors: Jing Wei , Zhang Jun Di , Liu Jia Chen , Wang Wei , Ren Mi
Published: March 2009

The joining of sintered ZrO2 to Al2O3 ceramics was realized using Al2O3-ZrO2-SiC interlayer
composites, which was designed according to the Al2O3-ZrO2-SiO2 ternary phase equilibrium diagram.
Effects of oxidizing SiC on joining were analyzed. The microstructure and components of the joints were
studied using XRD and SEM.
Consolidation of Porous Ceramics Using Protein Foam by Microwave Heating
Authors: Zhang Peng Yu , Liu Hai Yan , Liu Jia Chen , Fan Wei , Liu Chang
Published: March 2009

A simplified method, using microwave molding, to prepared zirconia porous ceramics was
proposed, which was involved in the use of albumen and zirconia in aqueous medium, consolidation
conducted by microwave heating, and sintering finally at elevated temperature. Microstructure and
properties of porous zirconia ceramics prepared by microwave molding were compared with those by
traditional heating consolidating process.
Joining of SiC Ceramic to Graphite Using Ni-51Cr Powders as Filler
Authors: Mao Yang Wu , Li Shu Jie , Yan Lian Sheng
Published: March 2009

Joining of SiC ceramic to graphite is important from both technical and economical points of
view. High temperature brazing of recrystallized SiC ceramic to high strength graphite has been realized
using Ni-51Cr (consisting of Ni + 51wt% Cr powders) powders as filler. The obtained maximum
three-point bending strength of joints is 32.3MPa, which is equal to 80.8% of the strength of the graphite.
Microstructure and phase analysis reveals that interdiffusions and chemical reactions take place in the
weld zone. A reaction layer and an interlayer form in the interfacial area. The reaction layer, of which the
thickness is about 60-100μm, is contacted with the SiC ceramic. The interlayer with the thickness of
about 200μm exists between the graphite and the reaction layer. The reaction layer is mainly composed of
Ni2Si, while the interlayer is mainly composed of Cr23C6 and Ni2Si.
On the Interface between Porcelain and Titanium
Authors: Guo Li Tong , Gao Ji Qiang , Liu Xiao Chen , Guo Tian Wen , He Zeng Ying
Published: March 2009

Low-fusing dental porcelain was fused on titanium surface. The adhesion between the titanium
and porcelain was evaluated by three-point flexure test. It was shown that the failure of the titaniumporcelain
predominantly occurred at the alloy-oxide interface. Rutile phase was present on the interface
debonding from porcelain. The influence of corrosion on bonding strength was also investigated. The
results suggested that, after being immersed in artificial saliva with pH of 2.7, 5.4 and 7.0, no decreasing
of the bonding strength of Ti-porcelain occurred.