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Journal of materials science & {2. 2010年第11期26卷 996-1000页

作者： Lihong Xue and Youwei Yan state key {2. of {3.s {3. and die and mould technology,huazhong university of science and technology,Wuhan {12.,{13. [a] state key {2. of {3.s {3. and die and mould technology huazhong university of {2. and{3. Wuhan 43.074 china

Highly oriented barium titanate （BaTiO 3. thin films on Pt substrate were fabricated by combination of electrophoretic deposition with hydrothermal *** structure and morphology of thin films were characterized by X-ray diffraction and field-emission scanning electron *** is found that the titania precursor film,Ba（OH）2.concentration and hydrothermal temperature play crucial roles in the film morphology and *** BaTiO3.thin films with highly （110） preferred orientation can be formed on polycrystalline Pt substrate by appropriate adjustment of the reaction *** orientation parameter f of highly oriented BaTiO3.films was up to *** films exhibited a smooth and crack-free surface and remained in the layered *** situ topotactic transformation and dissolution-crystallization mechanisms were proposed to explain the morphology and orientation of BaTiO3.films during hydrothermal treatment.

关键词： Barium titanate Preferred orientation Electrophoretic deposition Hydrothermal treatment

HCWCI/Carbon Steel Bimetal Liner by Liquid-Liquid Compound Lost Foam Casting

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Journal of Iron and Steel Research International 2012年第10期19卷 13-19页

作者： XIAO Xiao-feng1,2. YE Sheng-ping2. YIN Wei-xin3. XUE Qiong4 (1. School of Mechanical Engineering and Automation, Wuhan Textile university, Wuhan 43.073. Hubei,{3. {2., huazhong university of science and technology, Wuhan 43.074, Hubei,{3. 3. Wuhan Zhike Abrasive-Resistant material science and technology Development Co Ltd, Wuhan 43.073. Hubei,{3. 4. College of science, Wuhan university of technology, Wuhan 43.079, Hubei,{3.) [a] School of Mechanical Engineering and Automation Wuhan Textile University Wuhan 430073 Hubei China [b] state key {2. of {3. {3. and die and mould technology Huazhong University of Science and Technology Wuhan 430074 Hubei China [c] Wuhan Zhike Abrasive-Resistant material science and {2. Development Co Ltd Wuhan 430073 Hubei China [d] College of science Wuhan University of Technology Wuhan 430079 Hubei China

Impact, friction and corrosion from the grinding balls and the grinding medium during the mineral processing result in liner breakage. Liner, made from Hadfield steel or alloyed steel, could not have served in wet grinding environment for more than ten months. Composite liner, made from HCWCI (high Cr white cast iron) and carbon steel, has been developed successfully with liquid-liquid composing process based on LFC (lost foam casting). The microstructure of composite was analyzed with optical microscope, SEM (scanning electron microscope)/EDX energy-dispersive X-ray and XRD (X-ray diffraction). According to micrograph, the combination region of two metals was staggered like dogtooth, no mixtures occurred between two liquid metals, and its interface presented excellent metallurgical bonding state. The results of mechanical property test show that, the hardness of HRC, the fracture toughness, and the bending strength are more than 61, 16.5 J/cm2.and 1 600 MPa, respectively. Comparison between liners made from bimetal composite and alloyed steel has also been investigated in industrial hematite ball mill. The results of eight months test in wet grinding environment prove that the service life of bimetal composite liner is three times as long as that of one made from alloyed steel.

关键词： composite liner bimetal liquid-liquid compound composite interface lost foam casting high Cr white cast iron

Effect of bonding process on the properties of isotropic epoxy resin-bonded Nd-Fe-B magnets

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Rare Metals 2009年第3期28卷 248-252页

作者： ZHANG Xiuhai XIONG Weihao state key {2. of {3. {3. and die ＆ mould technology Huazhong University of Science and Technology Wuhan 430074 China

Bonded NdFeB magnets were prepared by compression molding. The effect of preparation technology on their magnetic and mechanical properties was studied through the analysis of density, Br, Hcj, （BH）max, bending strength, and compressive strength of the bonded magnets. The results showed that the magnetic properties decreased with increasing binder content, whereas the mechanical properties increased. Br and （BH）max increased with rising pressure, whereas Hcj decreased. For a fixed mass fraction of the binder, the optimal pressure was 62. MPa and the best thermosetting temperature was 160°C. These conditions made the bonded magnets have the optimal mechanical properties. Scanning electron microscopy （SEM） analyses of the fracture surfaces indicated that the epoxy resin bonded magnets exhibited brittle behavior.

关键词： Nd-Fe-B bonded magnets magnetic properties mechanical properties brittle behavior epoxy resin

Structure and Properties of TiB_2.Thin Films Deposited at Low Temperatures Using RF Magnetron Sputtering

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Journal of Wuhan university of technology({2.s{3.) 2008年第5期23卷 666-669页

作者：戴伟张同俊 state key Lab of {2. {3. and die & {3. technology Huazhong University of Science and Technology

The TiB2.thin films were deposited on steel substrates using RF magnetron sputtering technique with the low normalized substrate temperature （0.1〈Ts/Tm〈0.2.. Microstructure of these films was obtained by field emission scanning electron microscope （FESEM） and the grazing incidence X-ray diffraction （GIXRD） characterization, while the composition of films was obtained using Auger emission spectroscopy （AES） analysis. It was found that the TiB2.thin films were overstoichiometric with the B/Ti ratio at 2.3. and the diffusion of Ti and B atoms on the substrate surface was greatly improved at 3.0 ℃. Moreover, a new dense structure, named ＂equiaxed＂ grain structure was observed by FESEM at this substrate temperature, Combined with FESEM and AES analysis, it was suggested that the ＂equiaxed＂ grain structure was located in Zone 2.at the normalized substrate temperature as low as 0.18.

关键词： TiB2.thin films structure zones 1,2.T equiaxed structure superhard coating auger electron spectroscopy

Effects of Ce and Sb on the microstructure and properties of AZ91D magnesium alloy prepared by the EPC process

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Rare Metals 2008年第1期27卷 41-45页

作者： LI Jiqiang DONG Xuanpu FAN Zitian WANG Yuanqing state key {2. of {3. {3. and die ＆ mould technology Huazhong University of Science and Technology Wuhan 430074 China

The effects of small amounts of cerium and antimony additions on the microstructure and the mechanical properties of AZ91D（Mg-9Al-Zn） based alloy were researched via the expendable pattern casting（EPC） *** results show that the microstructure is obviously refined and the tensile strength of the AZ91D based alloy at ambient temperature is significantly *** compared to AZ91D,the AZ91D-1.0%Ce-0.4%Sb alloy has higher ultimate tensile strength and *** ultimate tensile strength and elongation are enhanced by 3.% and 47%,*** morphology of the tensile fracture of the AZ91D-1.0%Ce-0.4%Sb alloy has more characteristics of *** indicates that it has had a larger plastic deformation before *** tensile strength and elongation decrease with the increase of Ce and Sb contents because of the coarsening and volume increase of CeSb and Al11Ce3.phases.

关键词： AZ91D Ce Sb microstructure mechanical properties

Realizing Knowledge Reuse in Standard Parts Library Management System

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Computer Aided Drafting,Design and Manufacturing 2008年第1期18卷 32-38页

作者： YE Xiao-feng, LI Jian-jun (state key {2. of {3. {3. and die & mould technology, huazhong university of science and technology, Wuhan 43.074, china)

Knowledge reuse is a process for designing new product based on the embedded design knowledge and experience of existing products. In order to improve quality and efficiency of product design, a method to extract related knowledge from using standard parts in product design is introduced. Based on the characteristics of standard parts and their application, knowledge reusable standard parts library was built up through analysis of key techniques of standard part modeling such as knowledge expression, knowledge reuse and knowledge searching.

关键词： knowledge reuse standard parts library self-adaptation fast assembly

Voronoi Approach to Recursive Generation of Tool Path for SLS

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Computer Aided Drafting,Design and Manufacturing 2008年第2期18卷 13-20页

作者： QIAN Bo,ZHANG Li-chao,SHI Yu-sheng, LIU Bing (state key {2. of {3. {3. and die & mould technology, huazhong university of science and technology, Wuhan 43.074, china)

Assuming that a Voronoi diagram of slice area is obtained, topological structures of all Voronoi edges and Voronoi polygons are used to accelerate the offsetting process. Once walk line intersects with one of Voronoi edges of the starting Voronoi object, the next starting Voronoi object is acquired through the topology relationship. Experimental results show the approach is effective and simple.

关键词： CAD/CAM offsetting Voronoi diagram recursive selective laser sintering

Simulation of Gas-solid Two-phase Flow to Process of Filling the Foam mould

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Simulation of Gas-solid Two-phase Flow to Process of Filling...

Liquid-Gas Two-Phase Flow Simulation in Mold Filling Process with Level Set Method

第五届国际材料与热加工物理模拟及数值模拟学术会议

作者： Junxia JIANG1 a Zhichao WU2.b Liliang CHEN3.c state key {2. of material {3. and die & mould technology huazhong university of science and technology Wuhan {12.

In lost foam casting（LFC）,the foam pattern is the key qualification, and the filling process is one of the crucial processes to ensure the high quality of the foam pattern. Filling without uniformity and denseness will cause various defects and affect the quality of the surface. The influential factors of filling process are analyzed .And optimizing filling process, enhancing efficiency, decreasing waster are obtained by the numerical simulation of filling process using computer. The governing equations of the dense compressible gas-solid two-phase flow are established, and the physical signification of each one in the equations is discussed. The filling process is solved by Euler- Euler model. In the simulation, the volume of foam bead in every governing unit at different time is calculated, and the trend of foam bead flow is obtained. The filling process of various different conditions is simulated, considering different shooting methods and the position of baffles, and recorded by digital vidicon. The characteristics and the rules of the process are summarized. By contrasting the result of the numerical simulation with the one of examination, it is found that the fluid trend of foam bead in the numerical simulation is accordant to the actual process. So the numerical simulation of filling process by applying this model is an effective method.

关键词： lost foam casting foam pattern gas-solid two-phase flow filling process numerical simulation

来源： cnki会议评论

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Computer Aided Drafting,Design and Manufacturing 2008年第1期18卷 66-72页

作者： HAO Jing, CHEN Li-liang, ZHOU Jian-xin, LIAO Dun-ming (state key {2. of {3. {3. and die & mould technology, huazhong university of science and technology, Wuhan 43.074, china)

Air entrapped in liquid metal during the mold filling process seriously affects the casting quality, thus it is important to track its behavior in the mold cavity. A liquid-gas two-phase flow model is developed to describe the mold filling process and predict the air entrapment defect. The model is based on the combination of SOLA and Level Set Method. The pressure and velocity fields are calculated by SOLA,and the interface movement is simulated by Level Set method as the most common interface tracking method in recent *** order to validate the feasibility of the model,the liquid-gas two-phase simulation results were tested by the broken dam problem and the S-shaped experiment. Comparison between the experiments and simulation results show that Level Set method might be a very promising tool in two-phase flow simulation during the mold filling process.

关键词： level set method two-phase flow simulation mold filling casting

New Approach for 3. Shape Measurement Based on Color-Coded Fringe and Neural Network

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Computer Aided Drafting,Design and Manufacturing 2008年第2期18卷 50-56页

作者： QIN Da-hui, SHI Yu-sheng, WANG Cong-jun , LI Zhong-wei (state key {2. of {3. {3. and die & mould technology, huazhong university of science and technology, Wuhan 43.074, china)

A new 3. surface contouring and ranging system based on digital fringe projection and phase shifting technique is presented. Using the phase-shift technique, points cloud with high spatial resolution and limited accuracy can be generated. Stereo-pair images obtained from two cameras can be used to compute 3. world coordinates of a point using traditional active triangulation approach, yet the camera calibration is crucial. Neural network is a well-known approach to approximate a nonlinear system without an explicit physical model, in this work it is used to train the stereo vision application system to calculating 3. world coordinates such that the camera calibration can be bypassed. The training set for neural network consists of a variety of stereo-pair images and the corresponding 3. world coordinates. The picture elements correspondence problem is solved by using projected color-coded fringes with different orientations. Color imbalance is completely eliminated by the new color-coded method. Once the high accuracy correspondence of 2. images with 3. points is acquired, high precision 3. points cloud can be recognized by the well trained net. The obvious advantage of this approach is that high spatial resolution can be obtained by the phase-shifting technique and high accuracy 3. object point coordinates are achieved by the well trained net which is independent of the camera model works for any type of camera. Some experiments verified the performance of the method.

关键词： 3. shape measurement color-coded fringe neural network correspondence problem color imbalance