中文摘要：

利用基于密度泛函理论的第一性原理方法研究了金属元素Mo掺杂对TiAl合金体系力学性能的影响。根据计算得到的不同浓度掺杂体系的晶格常数、弹性常数、体弹模量及剪切模量发现,Mo掺杂能较好地改善TiAl合金的延性。从Mo掺杂后TiAl体系的分波电子态密度和电荷密度图,发现Ti原子的s、p、d电子均与邻近的Mo原子发生强烈的s-s、p-p、d-d电子相互作用,有效地束缚了合金中Ti和Al原子的迁移,有助于提高合金的稳定性和强度。

英文摘要：

The influence of Mo doping on the mechanical properties of TiAl alloy has been studied by the first-principles method based on density functional theory.According to the calculated lattice parameters,elastic constants,bulk modulus and shear modulus of the systems with different doping concentrations,we find that Mo doping can improve the ductility of TiAl alloy.The strong s-s,p-p and d-d electron interactions happen among all the s-,p- and d-electrons of Ti atom and near Mo atom,which astrict effectively the migration of Ti and Al atom and is beneficial to enhance the stability and strength of the alloy.