Growth of Spherical Void in Viscoplastic Medium under Tensile Dynamic Loading

A new evolution equation of growth of spherical voids in viscoplastic medium under dynamic tensile loading is presented in this paper. In the evolution equation, strain rate, local inertial effects and work-hardening behaviour of the material are taken into account, and the influence of these effects on the growth of voids numerically analyzed and discussed. The results of numerical analysis show that the growth of voids is highly sensitive to loading and strain rate. It is also shown that local inertial effects play an important role in the process of the void growth under high loading rate, and these effects become larger as loading rate increases. An expression of critical stress of the void growth is obtained.