Effects of alloying elements and temperature on the elastic properties of W-based alloys by first-principles calculations
Effects of alloying elements and temperature on the elastic properties of W-based alloys by first-principles calculations
复制标题
DOI：
10.1016/j.jallcom.2016.02.018
复制
发表时间：
2016-06
影响因子：
6.2
通讯作者：
Yong-Jie Hu;S. Shang;Yi Wang;K. Darling;Brady G. Butler;L. Kecskes;Zi-kui Liu
中科院分区：
文献类型：
--
作者：
Yong-Jie Hu;S. Shang;Yi Wang;K. Darling;Brady G. Butler;L. Kecskes;Zi-kui Liu
采用基于密度泛函理论的第一性原理计算方法研究了不同过渡合金元素（X）对W基合金弹性性能的影响。在此，考虑19种过渡金属合金元素（X）：Ti、V、Cr、Fe、Co、Ni、Y、Zr、Nb、Mo、Ru、Rh、Pd、Hf、Ta、Re、Os、Ir和Pt。结果表明：（i）稀相W-X合金的体积模量随平衡体积的增大而减小，尤其是合金元素在同一时期的体积模量减小;（ii）所有合金元素均使BCC W的剪切模量减小;（iii）合金元素Y使W的弹性模量减小最大。此外，它表明，由合金元素引起的W的弹性性能的变化是可追溯的电子电荷密度分布，导致W和合金原子之间的键畸变。采用基于德拜模型的准静态方法，预测了这些W-X合金在有限温度下的弹性性质。体心立方W和W-X合金的计算性能与实验测量值吻合良好。
The influence of various transition alloying elements (X's) on the elastic properties of W-based alloys has been studied via first-principles calculations on the basis of density functional theory. Here, nineteen transition metal alloying elements (X) are considered: Ti, V, Cr, Fe, Co, Ni, Y, Zr, Nb, Mo, Ru, Rh, Pd, Hf, Ta, Re, Os, Ir, and Pt. It is found that (i) the bulk modulus of the dilute W-X alloy decreases with increasing its equilibrium volume, particularly, for the alloying elements in the same period; (ii) all of the alloying elements decrease the shear modulus of BCC W; and (iii) the largest decrease of elastic properties of W is due to alloying element Y. In addition, it is shown that the changes of elastic properties of W caused by the alloying elements are traceable from the electron charge density distribution, resulting in a bonding distortion between W and the alloying atoms. Using the quasi-static approach based on the Debye model, the elastic properties of these W-X alloys at finite temperatures are predicted. Calculated properties of BCC W and the W-X alloys are in favorable agreement with available experimental measurements.