(南昌航空大学 航空制造工程学院，南昌 330063)
摘 要: 采用分子动力学方法研究Al2Cu的拉伸变形行为。建立Al2Cu分子动力学模拟模型，采用嵌入原子法模拟Al2Cu模型在常温、恒定工程应变速率的拉伸环境下对Al2Cu力学性能的影响，探讨温度和应变率对体系拉伸变形行为的影响。结果表明：发现Al2Cu非常脆，应变ε=0.086时应力达到峰值6.4 GPa，在拉伸初期不易产生位错，从而弹性变形阶段较长。Al2Cu对温度十分敏感，温度上升使Al2Cu的原子动能成倍增加，导致塑性变强但抗拉强度明显下降；Al2Cu在应变率为 为0.005~0.006 ps-1之间存在一个值，当Al2Cu的应变率超过这个值时，一些拉伸产生的空位来不及发生大幅移位，只能聚集在发射处附近，使体系内各处均出现大量孔洞。
关键字: Al2Cu；拉伸；分子动力学模拟；温度；应变率
（School of Aeronautical Manufacturing Engineering, Nanchang Hangkong University, Nanchang 330063, China）
Abstract:The tension deformation behavior of Al2Cu was studied by molecular dynamics method. The molecular dynamics simulation model of Al2Cu was established, and the influence of Al2Cu model on mechanical properties of Al2Cu under constant engineering strain rate tension at constant temperature was simulated by using the embedded atom method. The influences of temperature and strain rate on the tension deformation were discussed. The results show that Al2Cu is very brittle under that condition, when the strain is 0.086, the stress reaches the peak value of 6.4 GPa, and it is difficult to produce dislocations at the initial stage of tension, thus the elastic deformation stage is relatively long. Al2Cu is very sensitive to temperature. The kinetic energy of Al2Cu increases exponentially with the temperature rising, resulting in a stronger plasticity, but the tensile strength decreases obviously. The analysis also reveals a value between the strain rate of 0.005 to 0.006 ps-1, when the tensile strain rate of Al2Cu exceeds this value, some of the vacancies produced by stretching are too late to take place in the system, can only gather near the launch site, which leads to the formation of voids in the system.
Key words: Al2Cu; tension; molecular dynamics simulation; temperature; strain rate
