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Al-Sc合金相结构的第一原理研究苏振兴1,王雨晨1,王绍青1(1.辽宁省沈阳市科学院金属研究所沈阳材料科学国家(联合)实验室)摘 要:采用第一原理赝势平面波方法计算了Al-Sc合金固溶体,有序相和无序相结构对应的形成焓.在无序合金的电子结构研究中,引入了可以描述无序合金结构环境的小尺寸超单胞模型--SQS模型.计算结果表明:超饱和固溶体中的Sc原子具有偏聚产生L12结构的Al3Sc析出相和L10结构的AlSc析出相的趋势.依据对各相的电子结构及电子密度分析结果,初步探讨了时效处理导致超饱和固溶体Al(Sc)中......
:TN406 文献标志码:A First-principles calculations of doped elements on electromigration of Bi PANG Xue-yong, LIU Zhi-quan, WANG Shao-qing, SHANG Jian-ku (Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China) Abstract: The first-principles calculations on the elemental doping in SnBi lead-free solders were performed, aiming to inhabit......
South University, Changsha 410083, China) Abstract: Based on first-principles, the potential effects of coherent Al/θ′ interfaces under the response to external strains were calculated, and the effect...-stress aging; first-principles 时效强化(也称沉淀强化)作为一种最常见的热处理强化工艺,在各类合金材料,特别是航天航空用轻质结构合金材料中应用广泛.合金的时效强化效果,在很大程度上取决于时效过程中合金基体内强化第二相的析出数量,尺寸,分布弥散程度以及不同析出相的析出顺序.而析出相的析出序列可以随时效工艺参数(包括时效温度,时效时间,合金过饱和度等)的变化而发生改变,从而为......
利用第一性原理研究Ge:Si电子结构与光学性质 熊飞1,李亮1,杨瑞东1,刘芳1,杨宇1,王茺1 (1.云南大学工程技术研究院光电信息材料研究所,昆明,650091;2.红河学院物理系,蒙自,661100) 摘要:采用基于密度泛函理论的平面渡超软赝势方法和广义梯度近似,计算了掺杂Ge前后单晶Si中Si-Ge键的布居值,键长以及能带结构和态密度.计算结果表明,Ge掺杂后体系晶格常数发生变化,Ge-Si键变长,布居值及带隙宽度减小.还进一步研究了掺杂Ge后的光学性质,掺杂后静态介电常数值与纯Si相比有所增大,且吸收带宽变窄,吸收带边明显红移,并对这些掺杂诱导的材料物性变化进行了解释. 关键词:第一性原理; SiGe; 电子结构; 光学性质; first-principles study; SiGe; electronic structure; optical properties......
Elastic Properties and Stacking Fault Energies of Borides, Carbides and Nitrides from First-Principles CalculationsYong Zhang1,Zi-Ran Liu2,Ding-Wang Yuan1,Qin Shao1,Jiang-Hua Chen1,Cui-Lan Wu1,Zao-Li..., whose formation tendency can be measured using stacking fault energies(SFEs). The lower the SFEs, the easier the formation of twins. In the present study, by means of first-principles calculations, we......
pressure were investigated using first-principles calculations based on density-functional theory. Different forms of exchange-correlation functional including LDA, GGA and GGA+U were used... correlation; first-principles calculation; high pressure 1 Introduction As a prototype of Mott insulators and perfect candidate of antiferromagnetic material in FM-AFM exchange bias system [1], NiO has......
properties of Mg-2Zn-xCu alloys (x=0.5, 1.0 and 1.5, at.%) were investigated through microstructural and thermophysical characterization, heat treatment, and first-principles calculations. It was found... conductivities. Smaller amounts of Zn atoms dissolved in the matrix resulted in smaller lattice distortion and higher conductivities. The first-principles calculations findings also proved that the MgCuZn......
Trans. Nonferrous Met. Soc. China 27(2017) 148-156 First-principles investigations of structural, mechanical, electronic and optical properties of U3Si2-type AlSc2Si2 under high pressure Xu-dong... systematically investigated by using the first-principles calculations. The values of elastic constants and elastic moduli indicate that AlSc2Si2 keeps mechanical stability under high pressure. The mechanical......
J. Cent. South Univ. (2016) 23: 2173-2181 DOI: 10.1007/s11771-016-3274-y First-principles study on electronic structure, magnetic and dielectric properties of Cr-doped Fe3C YANG Jian-ping(杨建平), CHEN...-Verlag Berlin Heidelberg 2016 Abstract: The first-principles calculations were performed to investigate the electronic structure, magnetic and dielectric properties of Cr-doped Fe3C, in comparison......
Al-Mg合金中层错和孪晶形变能的第一性原理研究董明慧1,2,韩培德1,张彩丽2,杨艳青2,张莉莉2,李洪飞2(1.山西省太原市太原理工大学材料科学与工程学院2.山西省太原市太原理工大学新材料界面科学与工程教育部重点实验室)摘 要:通过基于密度泛函理论(DFT)的第一性原理计算了纯金属Al和Al Mg合金在(111)[112]滑移系的层错能和孪晶形变能,分析了Mg含量,占位对层错能和孪晶形变能的影响.计算选用了局域密度近似(LDA)和广义梯度近似(GGA PW91)2种近似方法,发现GGA PW91所获得的层错......
