【摘要】 针对金属材料的动态损伤现象,采用分子动力学方法对存在微观表面缺陷的材料在瞬态强冲击作用下的损伤情况进行数值模拟.模拟对象为铜材料,表面缺陷为锲形、圆形和方形沟槽,采用目前较为合理的嵌入原子势(EAM),并利用分子动力学程序(LAMMPS)进行动态数值模拟,有效地给出了存在不同微观表面缺陷的金属铜材料在瞬间强冲击作用下的损伤效应.结果表明,存在锲形缺陷的金属表面更容易发生微喷射现象,且微喷射速度随着锲形角增大而减小,随着冲击速率增大而增大.更多还原

【Abstract】 Aimed at various surface defects of the material,the micro-scale numerical simulation for dynamic damage under instantaneous impact is conducted.The embedded atoms method(EAM) potential and the molecular dynamics(MD) code LAMMPS are adopted.The shapes of surface defects are described as rectangle,round and groove,respectively.The damage effect of the copper material with various surface micro-scale defects under instantaneous impact was simulated effectively.The results show that the surface with groove defect is easier to induce the ejection of micro particles than the circular or square defects.The ejection velocity decreases with the increase of the groove angle,and increases with the increase of the impact speed.更多还原