温度对单晶铝裂纹扩展影响的分子动力学模拟

Effects of Temperature on Growth of Monocrystalline Aluminum Crack——a Molecular Dynamics Study

使用三维分子动力学方法模拟了单晶铝预制初始裂纹扩展过程,研究了裂纹扩展机理,及温度对裂纹扩展过程的影响。采用Morse势计算原子之间的相互作用关系。研究结果表明,裂纹尖端由于原子晶格发生重组发射位错,导致裂纹尖端出现畸变,裂纹开始扩展。温度对裂纹扩展过程中裂纹形貌、原子晶格变形程度、系统势能有显著影响。

Three-dimensional molecular dynamics simulations were performed to investigate the nature of pre-defined crack growth processes of monocrystalline aluminum, and the effects of temperature on the processes were studied. The Morse potential was utilized to compute the atomic interaction between aluminum atoms. The results show that dislocations are generated due to rearrangement of atom lattices; consequently aberrations are formed in the crack tip, which leads to the growth of crack. The temperature has significant effects on the crack profile, deformation degree of atom lattices, and system potential energy during the crack growth processes.