A void growth-based failure model to describe spallation

A new dynamic failure model to describe void nucleation, growth, and coalescence in ductile metals is reported. The model is based on a pressure-dependent yield criterion for compressible plastic flow. This three-dimensional, plasticity-based continuum damage model is incorporated into a finite difference, wave propagation code. A procedure to determine the failure model parameters is proposed. In this procedure, the model parameters are calibrated based on the ability to match the experimental free-surface velocity history with code simulations. Model parameters for oxygen-free high-conductivity copper have been determined successfully using this procedure.