论文部分内容阅读
利用嵌入原子法(EAM)势函数,采用分子静态弛豫方法得到了NiAl合金中Al空位、Ni空位、Al反位置缺陷和Ni反位置缺陷的形成能.通过平衡方程的建立及求解得到了各种点缺陷浓度随温度与组分的变化规律.研究结果表明,在NiAl合金中,当偏离化学计量比时,均存在“组分缺陷”.“组分缺陷”浓度基本不随温度变化,约在10-2~10-1数量级,而由原子热振动引入的“热缺陷”浓度随温度变化明显.NiAl合金的屈服强度和扩散系数随化学成分的变化,主要与不同化学成分合金的“组分缺陷”种类及浓度有关.
The formation energies of Al vacancy, Ni vacancy, Al anti-position defect and Ni anti-position defect in NiAl alloy were obtained by the method of molecular static relaxation using the EAM potential function. Through the establishment of the equilibrium equation and the solution, the variation rules of various point defects with temperature and composition were obtained. The results show that in the NiAl alloy, when deviating from the stoichiometric ratio, there are “component defects.” The concentration of “component defect” basically does not vary with temperature, which is on the order of 10-2-10-1, while the concentration of “thermal defect” introduced by atomic thermal vibration changes obviously with temperature. NiAl alloy yield strength and diffusion coefficient changes with the chemical composition, mainly with different chemical composition alloy “component defects” type and concentration.