Numerical study of spall fracture in solids subjected to high strain rate loading

摘要

Experimental and numerical investigations to understand the mechanisms of spall fracture of solids subjected to high strain rate loading have been going on for several decades. While microscopic studies of the fractured samples from experiments provide information on the final microstructure and distribution of the voids or cracks on the fractured surface, numerical simulations help construct and validate theories to explain the fracture phenomenon. In the present work, numerical simulations of plate impact are performed to study the role of fracture modes and thermal softening effects on the free surface velocity profiles. Two damage models based on critical mean stress and critical principal stress, representing ductile and brittle fracture respectively, are used for the target plate. The depth of pullback signals in the free surface velocity profiles are predicted for the above parameters.