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Fatigue Behavior of HDPE composite Reinforced with Silane Modified TiO_2

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Journal of Materials Science & Technology 2011年第7期27卷 659-667页

作者： c.x. Dong S.J. Zhu Mineo Mizuno Masami Hashimoto Department of Intelligent Mechanical Engineering Fukuoka Institute of Technology Fukuoka 811-0295 Japan Nanomaterials Laboratory Beihua University Jilin 132013 China Japan Fine ceramics center Nagoya 456-8587 Japan

The composite of high density polyethylene reinforced with silane-modified TiO2 particles （silane-TiO2/HDPE） is a potential bone substitute biomaterial. The structure, bioactivity, and mechanical properties of silane-TiO2/HDPE are analogous to those of natural bone, correspondingly. In order to investigate the effect of silane connection and saline solution on fatigue behaviors, flexural fatigue tests with this composite were carried out in both air and saline solution. Saline solution was found to have different effect on fatigue life. In saline solution, the fatigue life could be improved at stress levels lower than 30 MPa, while the fatigue life could be reduced at stress levels higher than 30 MPa. After analyzing the fracture morphologies, different failure mechanisms were proposed, and the important role of silane connection in the composite during the fatigue process was discussed. Silane connection cannot only support the loading stress but also hinder the failure process under loading effectively. For dry specimens, no interfacial failure between the filler and matrix was found. For wet specimens, it is inferred that the synergetic effect of saline solution and high concentrated stress at high stress level could easily destroy the silane connection, which accelerated the fracture process, whereas the synergetic effect of saline solution and silane connection at low stress level could promote the formation of more microcracks on sample surface, which hindered the final fracture.

关键词： Fatigue composites Polymers Fracture Interfaces

MIcROSTRUcTURE EVOLUTION AND MEcHANIcAL HARDENING OF HYPEREUTEcTOID PEARLITIc STEEL DURING cOLD ROLLING

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Acta Metallurgica Sinica(English Letters) 2007年第4期20卷 287-292页

作者： x. Zhang c.x. Wang x.M. Liu Q.N. Shi Key Laboratory of Advanced Materials of Yunnan Province Kunming University of Science and Technology Kunming 650093 China Institute for Structural Materials Central Iron and Steel Research InstituteBeijing 100081 China

The microstructure evolution of different cold rolling reductions （from 0 to 81.6%） was studied by SEM （scanning electron microscopy） and TEM （transmission electron microscope）. The study showed that the orientation multiplicity of pearlitic lamellas resulted in inhomogeneous deformation of different pearlitic lamellas, and with the increase of reduction, the microstructure underwent a course of ＂homogeneity → inhomogeneity → homogeneity＂. The result of xRD （x-ray diffraction） analysis indicated that cementite did not decompose and dissolve into ferrite; the results of the mechanical property test suggested that the relationship between Rp0.2 （yield strength） and ε （true strain） was in good agreement with Hollomon relationship. With the equation Rp0.2 = 1465ε^0.18, the yield strength of the steel in different reductions could be well predicted.

关键词： cold rolling hypereutectoid pearlitic steel microstructure evolution mechanical hardening

FUTURE OF HIGH TEMPERATURE MATERIALS FOR GAS TURBINE

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Acta Metallurgica Sinica(English Letters) 1996年第6期9卷 391-406页

作者： c.x. Shi(National Natural Science Foundation of china, Beijing 100083, china )

A comprehensive survey was made of various candidate high temperature materials for gas turbine use, and their relative merits and drawbacks were assessed. It is shown that superalloys, fine-tuned, will be persistent for the next few decades, to be followed up by high temperature intermetallics. For advanced ceramics, the problems of reliability and cost will have to be solved before they can be used in critical parts of *** are c/c composites with their oxidation problem. Surface modification and development of thermal barrier coatings can effectively overcome many problems of gas turbine materials and these technologies should be emphasized.

关键词： superalloy intermetallic compound ceramic c/c composite,surface modification

A cLASS OF FAcTORIZED QUASI-NEWTON METHODS FOR NONLINEAR LEAST SQUARES PROBLEMS

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Journal of computational Mathematics 1996年第2期14卷 143-158页

作者： c.x. xu x.F. Ma M.Y. Kong(Department of Mathematics, xi’an Jiaotong University, xi’an, china) 西安交通大学数学系陕西西安

This paper gives a class of descent methods for nonlinear least squares solution. A class of updating formulae is obtained by using generalized inverse matrices. These formulae generate an approximation to the second part of the Hessian matrix of the objective function, and are updated in such a way that the resulting approximation to the whole Hessian matrix is the convex class of Broyden-like up-dating formulae. It is proved that the proposed updating formulae are invariant under linear transformation and that the class of factorized quasi-Newton methods are locally and superlinearly convergent. Numerical results are presented and show that the proposed methods are promising.

关键词： BFGS A cLASS OF FAcTORIZED QUASI-NEWTON METHODS FOR NONLINEAR LEAST SQUARES PROBLEMS

EFFEcT　OF　DYNAMIc　REcRYSTALLIZATION　ON　SHAPE　MEMORY　EFFEcT　IN　Fe－Mn－Si　BASED　ALLOYS

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Acta Metallurgica Sinica(English Letters) 1996年第5期9卷 361-366页

作者： L.J. Rong Y. Y. Li and c.x. Shi(Institute of Metal Research, chinese Academy of Sciences, Shenyang 110015, china)

Improvement of shape, memory effect (SME) in Fe-Mn-Si based alloys has been investigated, compared with that by conventional 'training' treatment. It is found that SME in Fe-Mn-Si alloy can be greatly improved by ausforming and 3.8%recovery strain and 2.2% complete recovery strain can be reached by ausforming at 973 K when dynamic recrystallization has just occurred. The mechanism for the improvement of SME is proposed.

关键词： shape memory effect dynamic recrystallization Fe-Mn-Si based Alloy

FAcILE HYDROTHERMAL SYNTHESIS AND GROWTH KINETIcS OF Fe-BASED MAGNETIc NANOPARTIcLES

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Acta Metallurgica Sinica(English Letters) 2007年第6期20卷 434-440页

作者： c.x. You J.c. Zhang Y. Shen Z.W. Song Shool of Material Science and Engineering Shanghai University.Shanghai 200072 China

The facile hydrothennal method was used to synthesize Fe3O4 nanoparticles with an average diameter of 1 1nm. The pure body-centered cubic （bcc）-Fe nanoparticles were prepared by reduction of Fe3O4 nanoparticles powder in H2 atmosphere. The structure, morphology and magnetic＇properties of the products were characterized by x-ray powder diffraction （xRD）, transmission electron microscopy （TEM）, thermogravimetric analysis-differential scanning calorimetry （TGA-DSc） and vibrating sample magnetometer （VSM）. The results showed that the as-prepared Fe3O4 nanoparticles had a relatively homogeneous size. The particle diameters became bigger with the increase of reaction time. The growth kinetics of the Fe3O4 nanoparticles was also briefly discussed. The products exhibited superparamagnetic properties at room temperature and the specific saturation magnetization was dependent on the particle sizes.

关键词： Fe-based nanoparticle hvdrothermal specific saturation magnetization kinetics

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有关梅毒的临床特征

地方病译丛 1993年第2期14卷 47-50页

作者： c.x.Альмухаметов 白常乐

在原苏联,由于性病的发病率在急剧下降,一系列问题摆在了医生面前,其中包括对梅毒的临床和经过现状的精细研究,所有的专家对于梅毒的一些特点也应当有充分认识。我们观察了不同类型的梅毒病人254例,其中男性61.8%,女性38.2%。

关键词：梅毒临床特征症状

Theoretic and Numerical Study of a New chaotic System

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Intelligent Information Management 2010年第2期2卷 104-109页

作者： c.x. Zhu Y.H. Liu Y. Guo 不详

This paper introduced a new three-dimensional continuous quadratic autonomous chaotic system, modified from the Lorenz system, in which each equation contains a single quadratic cross-product term, which is different from the Lorenz system and other existing systems. Basic properties of the new system are analyzed by means of Lyapunov exponent spectrum, Poincaré mapping, fractal dimension, power spectrum and chaotic behaviors. Furthermore, the forming mechanism of its compound structure obtained by merging together two simple attractors after performing one mirror operation has been investigated by detailed nu-merical as well as theoretical analysis. Analysis results show that this system has complex dynamics with some interesting characteristics.

关键词： chaotic System Lyapunov Exponent Poincaré Mapping Fractal Dimension Power Spectrum

Microstructural characterizations of Maraging Steel Processed by Equal-channel Angular Pressing

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Microstructural Characterizations of Maraging Steel Processe...