中文摘要：

在不同负静压下对中心带有一个球形孔洞的面心立方金属铜进行分子动力学模拟,从晶体的形变,原子分布示意图,径向分布函数等方面进行讨论.发现在弱的负压下,孔洞及材料作弹性变形,超过一定阈值时出现塑性变形,并在局部出现相变.在极强的负压下,材料断裂.随拉伸应力的增加,材料经历弹性均匀拉伸——局部fcc到hcp的相变及缺陷的产生——缺陷积累产生微裂纹或空洞——材料断裂的过程.

英文摘要：

Molecular dynamics simulations are performed for a block copper with an orbicular hole in the center under minus static pressures. The distortions, characteristics of atoms and radial distribution functions are calculated. Under a small minus pressure, an elastic stretch distortion appears and as the pressure exceeds a certain value plastic deformation and local phase transformation are found. Under extreme minus pressure, the material fractures. As the minus pressure increases the material experiences complex procedures： from an uniform elastic stretch to a local fcc -hcp strnture transformation, then from a defect generation to a defect accumutation and finally a fracture forms.