Experimental examination and numerical NAG model analysis of spall sensitivity to microstructure in copper

Abstract

In order to achieve incipient and complete spallation, plane impact experiments were performed on three types of copper with different impurity levels. Dependence of the damage behavior on the material microstructure was found. The VISAR results of these experiments were used to examine the NAG model of Curran et al [Phys Rev. 147 (1987)], which includes a detailed description of microscopic void nucleation and growth dynamics. All measurements could be fitted by change of a single parameter in the model, the initial nucleation rate. The analysis demonstrates the competitive role of void nucleation and growth in the development of the spall.