DYNAMICALLY INDUCED PHASE-TRANSITIONS AND THE MODELING OF COMMINUTIONIN BRITTLE SOLIDS

Some experiments suggest the presence of a sharp interface between com minuted and uncomminuted regimes in a ceramic subject to impact by a p enetrator. This in turn suggests that one might model the associated d ynamical process with the help of recently developed continuum models of the macroscopic response of solids undergoing phase transitions. A highly idealized phase transition model of such a comminuted process i s analyzed here. The model accounts for the kinetics of the phase tran sition. If the shear wave speed in the comminuted material is small co mpared to that in the uncomminuted portion, it is found that the energ y reaching the uncomminuted portion of the target is greatly reduced i n comparison to its value in the absence of the phase transition.