A finite strain energetic analysis of the hollow sphere problem under hydrostatic loading

Abstract
The growth of a void in a sphere of an elastic perfectly plastic material submitted to an external hydrostatic loading is modeled in order to formulate a thermodynamically-based dynamic damage model. The case of infinitesimal strains is first studied, and it is shown that, for small initial void volume fractions, it leads to a gross overestimation of void growth kinetics. The framework of multiplicative elasto-plastic decomposition is used in the present work, and the analytical results compare exactly with numerical simulations carried out with the commercial FE code ABAQUS. A thermodynamic analysis is then performed, and will be considered as a basis for investigating thermal softening and micro-inertial effects on the damage process.