(α,β,γ)-Nb_5Si_3相的稳定性、弹性常数和热力学性质(英文)  

Stability, Elastic Constants and Thermodynamic Properties of(α, β, γ)-Nb_5Si_3 Phases

作　　者：段永华[1] 

机构地区：[1]昆明理工大学云南省新材料制备与加工重点实验室,云南昆明650093

出　　处：《稀有金属材料与工程》2015年第1期18-23,共6页Rare Metal Materials and Engineering

基　　金：National Natural Science Foundation of China(51201079)

摘　　要：采用第一性原理计算了金属间化合物α-Nb5Si3,β-Nb5Si3和γ-Nb5Si3的结构稳定性、弹性常数、热力学性质和电子结构,并利用Voigt-Reuss-Hill方法计算了弹性常数。结构参数优化结果与实验值基本一致;结合能和形成焓结果表明α-Nb5Si3的结构稳定性最好。最后分析和讨论了3种不同Nb5Si3相的延展性和弹性各向异性。First principles calculations have been carried out to investigate the structural stability, the elastic constants, the thermodynamic properties and the electronic structure of the intermetallic compounds α-Nb5 Si, β-Nb5 Si and γ-Nb5Si3. The optimized structural parameters are well consistent with the experimental values. Cohesive energy and formation enthalpy show that α-Nb5 Si has the strongest structural stability. The independent single-crystal elastic constants at zero pressure as well as polycrystalline elastic parameters have been calculated by Voigt-Reuss-Hill averaging scheme. The mechanical properties of the different Nb5Si3 phases such as ductility and elastic anisotropy were further analyzed and discussed.

关 键 词：Nb5Si3 第一性原理 弹性常数 热容 

分 类 号：TG111[金属学及工艺—物理冶金]