高压下Mg2Ni合金结构稳定性和弹性性质的第一性原理研究
First-principles calculation of structural stability and mechanical properties of Mg2Ni alloy under high pressure
肖雄 1逯来玉 1饶梓楚1
作者信息
- 1. 四川师范大学物理与电子工程学院,成都 610068
- 折叠
摘要
基于密度泛函理论的第一性原理,本文对不同压强下Mg2Ni合金的晶格结构和力学性能进行了计算和分析.计算结果表明:在0～60 GPa范围内,Mg2Ni的晶格常数和晶胞体积随压强增加而单调减小.Mg2Ni的弹性常数C11、C12、C13、C33 和C44 在0～35 GPa压强下满足稳定性判据,在40～60 GPa压强下不满足稳定性判据,表明机械性能不稳定.高压会增强Mg2Ni的体模量B、杨氏模量Y、剪切模量G.Mg2Ni的柯西压力、G/B和泊松比,均表明Mg2Ni在0～5 GPa压强下表现出脆性,在7～35 GPa压强下表现出延展性.
Abstract
The lattice constants,cell volumes and Mechanical properties of Mg2Ni alloy at different pressures were calculated and analyzed by the first-principles investigations.It was shown that lattice parameters and volume of Mg2Ni decreased gradually with increased pressures in the range of 0～60 GPa,and the elastic con-stant C11,C12,C13,C33 and C44 of Mg2Ni satisfied the stability criterion at 0～35 GPa pressure.The stability cri-terion was not satisfied at the pressure of 40～60 GPa,which suggest mechanical instability.The bulk modu-lus B,Young's modulus Y and shear modulus G of Mg2Ni all increased with the increase of pressure,which meant good mechanical properties in high pressure environment.The Cauchy pressure,G/B and Poisson's ra-tio of Mg2Ni showed that Mg2Ni exhibited brittleness at pressure of 0～5 GPa and ductility at pressure of 7～35 GPa.
关键词
Mg2Ni合金/力学性能/第一性原理Key words
Mg2Ni alloy/Mechanical properties/First-principles引用本文复制引用
基金项目
国家自然科学基金(50952025)
四川省大学生创新训练项目(S202310636137)
四川师范大学科研项目(024-341055001)
出版年
2024
国家科技期刊平台
NSTL
万方数据