First-principles investigation of electronic, mechanical and thermodynamic properties of L12 ordered Co3(M, W) (M = Al, Ge, Ga) phases
First-principles investigation of electronic, mechanical and thermodynamic properties of L12 ordered Co3(M, W) (M = Al, Ge, Ga) phases
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L12 有序 Co3(M, W) (M = Al, Ge, Ga) 相的电子、机械和热力学性质的第一性原理研究
DOI：
10.1016/j.actamat.2013.05.032
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发表时间：
2013-08
期刊：
影响因子：
9.4
通讯作者：
Zi-Kui Liu
中科院分区：
文献类型：
--
作者：
Yi Wang;Cuiping Wang;Xingjun Liu;Zi-Kui Liu
通过第一性原理计算，对Co3(M, W) (M=Al, Ge, Ga)相的平衡结构、温度相关的力学和热力学性质进行了研究。基态弹性常数的结果表明Co3(M,W)相机械稳定并具有固有的延展性。研究发现Co3(Ge,W)相的弹性耐热性能比Co3(Al,W)和Co3(Ga,W)相差。分析电荷密度差可以解释，Co3(Ge, W)的机械性能急剧下降主要是由于高温下Co-Ge键合减弱所致。使用通用指数讨论了作为温度函数的弹性各向异性。观察到Co3(M,W)相表现出高度的弹性各向异性。 Co3(M,W)的弹性各向异性程度可以通过温度的升高而显着降低。考虑振动和热电子的贡献，用准谐波声子方法处理晶格振动。计算热力学性质作为温度的函数，无需任何可调参数，包括热容、熵、焓和热膨胀系数。
Studies were carried out on the equilibrium structural, temperature-dependent mechanical and thermodynamic properties of the Co3(M, W) (M=Al, Ge, Ga) phases in terms of first-principles calculations. The results of the ground-state elastic constants revealed that Co3(M, W) phases are mechanically stable and possess intrinsic ductility. It was found that the elastic heat-resistant properties of Co3(Ge, W) phase are inferior to those of Co3(Al, W) and Co3(Ga, W). Analyzing the charge density difference provides the explanation that the sharp decrease in mechanical properties is mainly due to the weakening of Co–Ge bonding at elevated temperatures for Co3(Ge, W). The elastic anisotropy as a function of temperature is discussed using a universal index. It is observed that Co3(M, W) phases show a high degree of elastic anisotropy. The degree of elastic anisotropy could be significantly decreased by an increase in temperature for Co3(M, W). The lattice vibration is treated with the quasiharmonic phonon approach, considering both the vibrational and thermal electronic contributions. The thermodynamic properties as a function of temperature are computed without any adjustable parameters, including heat capacity, entropy, enthalpy and thermal expansion coefficient.
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DOI：
10.1115/1.3423687
发表时间：
1974
期刊：
--
影响因子：
--
作者：
E. Schreiber;O. Anderson;N. Soga;J. Bell
通讯作者：
E. Schreiber;O. Anderson;N. Soga;J. Bell
L12有序Co3(Al,W)沉淀物的结构稳定性和弹性性能
影响因子：
4
作者：
通讯作者：
--
影响因子：
8.6
作者：
Dipanjan Sen;C. Thaulow;S. Schieffer;Alan Cohen;M. Buehler
通讯作者：
Dipanjan Sen;C. Thaulow;S. Schieffer;Alan Cohen;M. Buehler
影响因子：
4.4
作者：
Born, M
通讯作者：
Born, M
影响因子：
3.7
作者：
Shang, Shunli;Wang, Yi;Liu, Zi-Kui
通讯作者：
Liu, Zi-Kui