Effect of osmium substitution on structural, electronic, mechanical, and thermodynamic properties of W-Os alloys: A first-principles study

作者：Chen, Yun; Tang, Lu; Cai, Houdao; Zhang, Meiyun; Wang, Xunjie; Jiang, Diyou^*

来源：Journal of Materials Research, 2023, 38(3): 883-893.

DOI：10.1557/s43578-022-00874-x

• Alloy
• Elastic properties
• Ductility
• Thermodynamics
• Debye temperature
• Electronic structure

In this paper, four W-Os alloys are designed, namely W0.9375Os0.0625, W0.875Os0.125, W0.8125Os0.1875, and W0.75Os0.25 alloys. Based on the analysis of the formation enthalpy and phonon spectrum, the W0.8125Os0.1875 and W0.75Os0.25 alloys are thermodynamically unstable. Therefore, this paper only studies the mechanical and thermodynamic properties of pure W, W0.9375Os0.0625, and W0.875Os0.125 alloys. The results show that W0.9375Os0.0625 and W0.875Os0.125 alloys still keep the cubic crystal system, and the lattice constants of pure W are reduced by doping Os. Based on the mechanical parameter analysis, the doping of Os reduces the stiffness of pure tungsten, but improves its strength. The B/G ratios of W0.9375Os0.0625 and W0.875Os0.125 alloys are higher than that of pure W, which indicates that Os doping can increase the ductility of pure tungsten. The W0.875Os0.125 alloy has anisotropic characteristics. However, the W0.9375Os0.0625 alloy has isotropic characteristics, which also shows that Os doping can improve the anisotropy of pure tungsten.

• 单位
  南昌航空大学