Ni中空位的计算机模拟

Computer Simulation of Vacancies in Ni

本文采用嵌入原子臭型的原子势,用分子动力学方法对纯 Ni 中单空位和双空位进行了计算机模拟实验.计算出单空位的形成能和迁移激活能分别为1.68eV 和1.14eV,双空位的结合能和迁移激活能分别为0.34eV 和0.64eV.发现单空位最近邻原子向着空位中心驰豫最近邻原子距离的0.324%,第二近邻原子背向空位中心驰豫0.381%,第三近邻原子向空位中心驰豫0.036%同时,详细分析了双空位近邻原子的位移场.本文所得的结果与实验数据符合相当好.

In this paper,the molecular dynamics is used to simulate mono-vacancyand divacancy in Ni with the embedded atom method.Calculated formationenergy and migration energy of mono-vacancy are 1.68 eV and 1.14 eVrespectively,and binding energy and migration energy of divacancy are0.34 eV and 0.64 eV respectively.It is found that the nearest-neighboratoms of mono-vaeancy relax inwards by 0.324% of the distance betweennearest neighbor atoms,the second neighbor atoms relax 0.381% outwardsand the third neighbor atoms relex 0.036% inwards.Meanwhile,thedisplacement fields of the neighbor atoms of divacancy are analysed indetail.The results are found to be in excellent agreement with theexperimental measurements.