材料期刊网

Tensile properties of Cu with deformation twins induced by SMAT

Jinyu GUO , Ke WANG , Lei LU

材料科学技术（英）

High density nano-scale deformation twins were introduced in the surface layer of Cu sample by means of surface mechanical attrition treatment (SMAT) at room temperature. The Cu sample with deformation twins shows a yield strength of about 470 MPa in tension tests. The significant strengthening may be attributed to the effective inhibition of slip dislocations by abundant twin boundaries.

关键词: Copper , 表面机械研磨 , 变形孪晶 , 强化

La对Fe-P-N合金Snoek-Ke-K■ster峰的影响

戢景文 , 魏全金 , 张国福 , 赖祖涵 , 陈廷国

金属学报

研究了F? P—N合金加?对Snoek—Ke-Koster(SKK)峰的影响,发现与合金含La,P的原子浓度比(C_(La)/C_p)有关:对于C_(La)/C_p较大(例如4.56和2.6)的合金,La有明显增强SKK阻?效应:对于C_(La)/C_p=0.27的P过饱和合金,La对SKK峰无明显影响。

关键词: 内耗 , Snoek-Ke-Koster peak , Fe-P-La-N alloy

Two-step magnetization in a spin-chain system on the triangular lattice: Wang-Landau simulation

Physical Review B

The Wang-Landau algorithm is used to study the thermodynamic and magnetic properties of triangular spin-chain system based on two-dimensional Ising model in order to understand the magnetic-order dynamics in Ca(3)Co(2)O(6) compound. The calculated results demonstrate that the equilibrium state of the rigid spins produces the two-step magnetization curve at low temperature even when the random-exchange term is considered. This work indicates that the four-step magnetization behavior observed experimentally must be due to the nonequilibrium magnetization.

关键词: calcium compounds;exchange interactions (electron);Ising model;magnetisation;thermodynamics;one-dimensional ca3co2o6;density-of-states;compound ca3co2o6;phase-diagram;proteins;crystal

SNOEK-Ke-K■STER PEAK OF INTERNAL FRICTION IN Fe-P-N ALLOYS

Y.Y.Che , G. Y.Zeng , Y. C. Xu and J. W , Ji(College of Science , Northeastern University , Shenyang 110006 , China)

金属学报(英文版)

The internal friction and precipitate phases of the deformed Fe-P-N alloys have been investigated. It has been found that the ratio of depends on the content of P and the relation holds if the content of N is lower than 30wt.ppm and the content of P is lower than 640wt.ppm. It shows that the intercept K2 is related to the presence of the atomic pairs and clusters of P in the alloy matrix.

关键词: internal friction , 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

EFFECT OF RARE EARTH ON MEDIUM-TEMPERATURE INTERNAL FRICTION OF COMMERCIALLY PURE IRON

JI Jingwen LAI Zuhan WU Yuqin ZHANG Guofu Northeast University of Technology , Shenyang , ChinaLI Guangyi Institute of Metal Research , Academia Sinica , Shenyang , China

金属学报(英文版)

The strong effect of rare earth(RE)on medium-temperature internal friction(IF)of commercially pure iron is closely related to the heat treatment.The RE added into iron has an alloying effect.The Snoek-Ke-Kster(briefly SKK)peak lower as the aging temperature in- creases from 150℃ to 450℃,but it still exists even aged at 600℃.However,the SKK peak temperature T_p does not simply falls as the ascending of aging temperature,it rises again at 600℃ aging.

关键词: internal friction , null , null

硅脂导热涂层改善LED散热性能的研究

张淑芳 , 方亮 , 付光宗 , 董建新 , 陈勇

材料导报

研究了导热硅脂(KE3493)涂层对水下密闭环境下应用的LED灯散热情况的影响,结果表明,LED系统的集成电路板上加入导热涂层能提高LED系统的散热效率,研究结果为导热涂层应用于LED散热系统提供了参考数据.

关键词: 导热涂层 , 散热性能 , LED , 硅脂

BORON ISOTOPE FRACTIONATION DURING PROLONGED ION-BOMBARDMENT

Chinese Physics Letters

Dynamic Monte Carlo simulation is used to explore the B isotope sputtering during 1 ke V Kr ion irradiation. It is found that at both zero and high fluences the light isotope is preferentially ejected in the near-normal direction; meanwhile, there is a low fluence (1.4 x 10(15) ions/cm2), at which the isotope fractionation is independent of the emission angle in the nearly whole angular range.

关键词: simulation

Effect of interstitial hydrogen on cohesive strength of Al grain boundary with Mg segregation

材料科学技术（英）

The effect of interstitial hydrogen on the cohesion of the Al Sigma=11(113) grain boundary (GB) is investigated based on the thermodynamic model of Rice-Wang using the first-principles density function calculation. The results indicate that interstitial H behaves as an embrittler from "strengthening energy" analysis. The reduced GB cohesion due to the presence of H at the GB is attributed to the low affinity between H and Al, and the weakened bonding of Al atomic pairs perpendicular to GB plane.

关键词: hydrogen;grain boundary;Al-Mg alloys;pseudopotentials;1st-principles

Effect of Interstitial Hydrogen on Cohesive Strength of Al Grain Boundary with Mg Segregation

Xiaoguang LIU , Xiaowei WANG

材料科学技术（英）

The effect of interstitial hydrogen on the cohesion of the Al ∑=11(113) grain boundary (GB) is investigated based on the thermodynamic model of Rice-Wang using the first-principles density function calculation. The results indicate that interstitial H behaves as an embrittler from "strengthening energy" analysis. The reduced GB cohesion due to the presence of H at the GB is attributed to the low affinity between H and Al, and the weakened bonding of Al atomic pairs perpendicular to GB plane.

关键词: Hydrogen , null , null