材料期刊网

SCALING PROPERTIES OF INTERFACES IN CRYSTALS UNDER NONEQUILIBRIUM CONDITIONS

D. W Shi , J. Y Huang and Q. W Long(International Centre for Materials Physics , Institute of Metal Research , Chinese Academy of Sciences , Shenyang 110015 , China Laboratory of Atomic Imaging of Solids , Institute of Metal Research , Chinese Academy of Sciences , Shenyang 110015 , ChinaState Key Laboratory for Fatigue and Fracture of Materials , Institute of Metal Research , Chinese Academy of Sciences , Shenyang 110015 , China )

金属学报(英文版)

We proposed an equation of Langevin type to describe the interface evolution in crystals under nonequilibrium conditions(such as in Cu-Fe or Cu-Co system upon ball miling). The scaling property (H) of this equation is in good agreement with the Monte Carlo simulations decribed by Bellon and Averback. In this equation the volume dchsion and intedece diffusion are all important and this is consistent with some experimental results.

关键词: scaling , null , null , null

Ion sputter erosion in metallic glass-A response to "Comment on: Homogeneity of Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass" by L-Y. Chen, Y-W. Zeng, Q-P. Cao, B-J. Park, Y-M. Chen, K. Hono, U. Vainio, Z-L. Zhang, U. Kaiser, X-D. Wang, and J-Z Jiang J. Mater. Res. 24, 3116 (2009)

Journal of Materials Research

The morphology of the dark and bright regions observed by transmission electron microscopy for the Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass strongly depends on the ion beam parameters used for ion milling. This indicates that the ion beam could introduce surface fluctuation to metallic glasses during ion milling.

关键词: room-temperature

CURRENT STATUS OF HIGH-RESOLUTION ELECTRON-MICROSCOPY AND ITS APPLICATIONS TO MATERIALS SCIENCE AND CONDENSED MATTER PHYSICS

材料科学技术（英文）

The present paper summarizes the current status of high resolution elect;on microscopy ( HREM) and the applications of HREM to materials science and condensed matter physics. This review recounts the latest development of high resolution electron microscope, progress of HREM and the applications of HREM, including the crystal structure determination of microcrystalline materials and characterization of the local structure of the defects and nanostructured materials as well as qualitative and quantitative analysis of the grain boundaries, interfaces and interfacial reactions in the advanced materials by means of HREM in combination with electron diffraction, subnanometer level analysis, image simulation and image processing.

关键词: juxtaposed pentagonal antiprisms;two-dimensional quasicrystal;domain;boundary structures;close-packed phases;nanocrystalline materials;crystal-structure;copper oxidation;initial-stage;translational;symmetry;rotational symmetry

Current Status of High Resolution Electron Microscopy and Its Applications to Materials Science and Condensed Matter Physics

Douxing LI and Hengqiang YE (Laboratory of Atomic imaging of Solids , Institute of Metal Research , Chinese Academy of Sciences , Shenyang , 110015 , China)

材料科学技术（英文）

The present paper summarizes the current status of high resolution electron microscopy (HREM)and the applications of HREM to materials science and condensed matter physics. This review recounts the latest development of high resolution electron microscope, progress of HREM and the applications of HREM, including the crystal structure determination of microcrystalline materials and characterization of the local structure of the defects and nanostructured materials as well as qualitative and quantitative analysis of the grain boundaries, interfaces and interfacial reactions in the advanced materials by means of HREM in combination with electron diffraction,subnanometer level analysis, image simulation and image processing.

关键词:

Mean-field theory for ferroelectricity in Ca(3)CoMnO(6)

Physical Review B

An elastic Ising model for CoMnO(6) chain is proposed to explain the ferroelectricity induced by collinear magnetic order in Ca(3)CoMnO(6), and then a mean-field theory with interchain spin interactions based on this model is developed. With inclusion of the dynamics of polarization domains at finite temperature, we address the rationality of our theory by the good agreement of the calculated electric polarization and dielectric susceptibility with the reported data on Ca(3)Co(2-x)Mn(x)O(6) (x approximate to 0.96) [Y. J. Choi, H. T. Yi, S. Lee, Q. Huang, V. Kiryukhin, and S.-W. Cheong, Phys. Rev. Lett. 100, 047601 (2008)], a typical diatomic Ising spin chain system, while the predicted magnetic susceptibility shows some difference from experiment, the reason of which is discussed.

关键词: calcium compounds;cobalt compounds;dielectric polarisation;ferroelectricity;Ising model;magnetic susceptibility;multiferroics;optical susceptibility;one-dimensional oxides;magnetic-properties;multiferroics;ca3co1+xmn1-xo6

Microstructure characterization of long W core SiC fiber

材料科学技术（英文）

Microstructure of SiC fiber manufactured by chemical vapor deposition (CVD) onto tungsten (W) wire core was investigated by analytical electron microscopy (AEM). The results reveal that the fiber consists of W core, SiC sheath and C-coating. SiC sheath could be subdivided into two parts according to whether containing C rich stripe, or not. An emphasis was put on W/SiC interfacial reaction products and the transition zone between sub-layers in SiC sheath. The W/SiC interface consists of three layers of reaction production, namely, W2C, W5Si3 and WC. And there are amounts of facet faults existing in (100) face of WC crystalline and two classes of stack faults in WC have been revealed. The formation essence of different sublayers in SiC sheath was also discussed.

关键词: siC fiber;chemical vapor deposition (CVD);analytical electron;microscopy (AEM);C-rich zone;reaction products;chemical vapor-deposition;silicon-carbide;model;dichlorodimethylsilane;interface;pyrolysis;hydrogen;strength

Study on the Relationship Between J-Integral and COD

Y.G. Cao , X.Y. Sun

金属学报(英文版)

J-integral and crack opening displacement δ(COD) were important parameters for characterization of fractures in engineering materials. The relationship between J-integral and COD has been investigated for a long time and was enerally represented as J = m σyδ, where σy is the yield strength and m is a function of specimen geometry and material properties. To determine the value of m, extensive studies and experiments have been performed. The method that used the fracture-surface topography analysis (FRASTA) for determining J-integral from fracture surfaces of materials was introduced. On the basis of the relationship between COD and fracture surface average profile, the relationship between J-integral and COD was deduced and compared with the generally used equation. The method was experimentally confirmed to be able to provide a new way to determine the relationship between J-integral and COD.

关键词: FRASTA , null , null

S355J2W耐候钢的耐腐蚀性能

鲁二敬 , 卢峰华 , 许鸿吉 , 谢明 , 钮旭晶

机械工程材料

通过周期浸润腐蚀试验，对比研究了S355．12W耐候钢和Q345R低合金钢在NariSOs溶液中的耐腐蚀性能，并用扫描电镜对腐蚀产物进行了观察和分析。结果表明：在相同试验条件下，S355J2W耐候钢的腐蚀速率低于Q345R钢的；S355J2W耐候钢会在表面形成黑褐色锈层，而Q345R钢表面形成橘红色易剥落的疏松锈层；S355J2W耐候钢腐蚀产物微观形貌为沿放射性方向生长的针状晶体，Q345R钢为颗粒状聚合物堆积而成，形状无规则，颗粒之间有较大的空隙。

关键词: S355J2W耐候钢 , 周期浸润腐蚀试验 , 耐腐蚀性能

Long periodic structure in ZrO2-Y2O3 ceramics

材料科学技术（英文）

A new type of long periodic structure has been found in ZrO2-Y2O3 ceramics in annealed states. High resolution electron microscopy (HREM), selected area electron diffraction, and computer simulation have been used to reveal the presence of the long periodic structure. The unit cell of the long periodic structure consists of a cubic ZrO2 unit cell and L1(0)- like phase one.

关键词: ceramics;electron diffraction;electron microscopy;crystal structure;microstructure

Long Periodic Structure in ZrO2-Y2O3 Ceramics

Jiancun RAO , Yu ZHOU , Douxing LI

材料科学技术（英文）

A new type of long periodic structure has been found in ZrO2-Y2O3 ceramics in annealed states. High resolution electron microscopy (HREM), selected area electron diffraction, and computer simulation have been used to reveal the presence of the long periodic structure. The unit cell of the long periodic structure consists of a cubic ZrO2 unit cell and L10- like phase one.

关键词: Ceramics , null , null , null , null