CONSTITUTIVE MODELING OF SHOCK RESPONSE OF PTFE

Polytetrafluoroethylene (PTFE) is a complex semicrystalline polymer with four pressure and temperature dependent crystalline phases. As has been recently studied, the crystalline region grows with load. Shock‐wave profiles reported from embedded gauges demonstrate features that may be related to impedance mismatches between the regions subjected to some transitions resulting in density and modulus variations. We consider the amorphous‐to‐crystalline and the high‐pressure Phase II–III transitions in the current simulation analysis. The present work utilizes a multi‐phase rate sensitive model to describe shock response of the PTFE material. One‐dimensional experimental shock wave histories are compared with calculated profiles using kinetics describing the transitions. The objective of this study is to understand the role of the various transitions in the shock response of PTFE.