银合金化镁钙合金中 AgMg、Mg2 Ca 和 AgCa 相的第一性原理计算

摘要

采用基于密度泛函理论(DFT)的 Materials Studio 中的 CASTEP 模块，对银合金化镁钙合金中 AgMg、Mg2 Ca、AgCa 相的热力学性质、电子结构和弹性性质进行了第一性原理计算，将计算得到的合金形成热、结合能、体模量、剪切模量、弹性模量、泊松比、熔点和硬度与文献值进行了对比。结果表明：AgMg 相的结合能力最强，结构最稳定，抵抗变形能力和抗剪切能力最强，熔点和硬度最高；AgCa 相的塑性和延展性要高于其它两相的；计算结果与文献值相差不大，证明了计算结果的正确性。%Based on density functional theory (DFT ) of CASTEP module from Materials Studio, thermodynamic,electronic structure and elastic properties of AgMg,Mg2 Ca and AgCa phases were calculated by means of first principle.Alloy formation energy,binding energy,bulk modulus,shear modulus,elasticity modulus, Poisson′s ratio,melting point and hardness obtained by calculating were compared with the values from literatures. The results show that,AgMg phase has the strongest alloying ability and structural stability,the strongest ability to resist deformation and shear capacity,the highest melting point and hardness;Plasticity and ductility of AgCa phase are better than that of AgMg and Mg2 Ca phases.The small difference between calculated results and literatures values proves the correctness of the calculated results.