Dynamic analysis on microvoid growth in viscoelastoplastic materials under thermal shock

The microvoid growth in an infinite medium under thermal shock was analyzed on the basis of the viscoelastoplastic theory. In the mathematical model of the problem, the stage of purely viscoelastic deformation was taken into account. The direct integration method is used to find the analytical expressions of displacement and stress. The moving interface between the viscoelastic and the viscoplastic zones was involved, and its location was determined by the nonlinear ordinary differential equation with initial condition. As an example, the evolution of void with time for the aluminum alloy material was investigated by numerical computation. The effects of the temperature variation, the heating rate, and the viscosity of material on the void growth were examined. The analysis indicated that the relationship between void growth and temperature load is nonlinear due to the appearance of moving interface.