纳米丝应变率和尺寸效应的数值模拟

在绝对零度下,利用基于分析型嵌入原子势的分子动力学模拟了体心立方(BCC)结构的纳米丝在不同应变率、和不同截面尺寸下的的拉伸变形过程,结果表明:在拉伸过程中,纳米丝表面出现了滑移带,并沿010方向发生脆性断裂;不同应变率只影响试样的断裂强度,应变率越大,断裂强度越高;而截面尺寸越大,屈服强度降低,断裂强度和弹性模量增大.

Simulation of the Strain Rate Effcet and Size Effect for Nanowires

The strain rate effect and size effect of nanowires were studied by molecular dynamics simulation, it's based on the embedded atomic potential. The results showed: during the stretching agenda , Shear band was observed and the brittle fracture was taken place along <010> direction. The strain rate only effected the fracture strength, with the increase of strain rate , the fracture strength increased accordingly. As the cross section size increased,the yield strength will decrease ,the Young's modulus and fracture strength will increase correspondingly.