摘要
采用第一原理赝势平面波方法计算了Ir合金化前后γ-Ni/γ′-Ni3Al相界的电子与能态结构,并比较了Ir元素分别占据不同亚点阵位时对相界断裂强度的影响。结果表明Ir优先取代Ni原子,其次是Al原子,较难占据间隙位。Ir取代Ni或Al位时,可以提高γ-Ni/γ′-Ni3Al相界的断裂强度,但提高有限。电子态密度与电子密度分布图显示,Ir合金化对γ-Ni/γ′-Ni3Al相界的强化的原因是Ir与其最近邻Ni原子间的电子相互作用引起的相界区域层间原子价键强度的增强。
Using the first principles plane-wave pseudopotential method, the energetic and electronic structure of Ni/Ni3 Al interface with Ir addition were calculated. The influence of Ir atom occupy different sub lattice on the interfacial fracture strength were compared. The results show that Ir preferentially substitutes Ni atoms, followed by A1 atom, but is difficult to occupy the interstitial sites. The substitution of Ir for Ni or of Al atom can improve the fracture strength of Ni/Ni3 A1 phase boundaries, but the extent of improvement is small. The analysis of electron densities of states （IX）S） and the distributions of valence electron densities of Ni/Ni3 Al interface reveal that the strengthening effect of Ir on the rupture strength of Ni/Nia A1 interface can be attributed to the enhancement of the interlayer bonding, which is induced by the strong interaction between the Ir-Ni atoms.
基金
陕西理工学院人才启动项目(SLGQD13-20)
