Evolution of the metal microstructure and conditions of strain localization under high-strain-rate loading

Specific features of evolution of the microstructure of coarse-grained and fine-grained copper are examined on the basis of an available dependence of the critical parameters of strain localization on the grain size, which was derived in an explosive collapse of hollow thick-walled cylinders. Similarity of the properties and mechanisms of deformation of fine-grained and ultrafine-grained materials is established. Based on the analysis of the results obtained, a scenario of the change in deformation mechanisms of fine-grained copper in the course of the development of deformation structures under high-strain-rate loading is proposed.