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利用嵌入原子法（ＥＡＭ）势函数，通过分子静态弛豫方法对ＮｉＡｌ合金中各种点缺陷的形成能进行了模拟计算．结果表明，从点缺陷的形成能来看，在ＮｉＡｌ晶格中很难形成Ｎｉ反位置缺陷，而Ａｌ原子亚点阵位置总是被占据．当合金富Ｎｉ时，Ｎｉ占据Ａｌ位置形成Ａｌ的反位置缺陷；当合金富Ａｌ时，形成Ｎｉ空位．点缺陷周围原子的位移情况及双空位形成能与空位之间间距的关系的研究表明，随着两个空位之间距离的增大，其交互作用逐渐减小并有互不影响的趋势．点缺陷和晶界的交互作用表明，ＮｉＡｌ晶界有吸收点缺陷以减低其晶界能，保持其晶界化学计量比结构的趋势．
The formation energies of various point defects in NiAl alloy were simulated by using molecular static relaxation method by using the EAM potential function. The results show that the formation of point defects from the point of view, in the NiAl lattice is difficult to form Ni anti-position defects, and Al atoms sub-lattice position is always occupied. When the alloy is rich in Ni, Ni occupies the Al position to form the anti-position defect of Al; when the alloy is rich in Al, Ni vacancies are formed. The study on the displacement of atoms around point defects and the relationship between the formation of double vacancy and the gap between vacancies shows that the interaction between two vacancies decreases gradually with no influence on each other. The interaction between the point defects and the grain boundaries shows that the NiAl grain boundaries have absorption point defects to reduce their grain boundary energy and maintain their grain boundary stoichiometric structure.