An Internal State Variable Elastoviscoplasticity-Damage Model for Irradiated Metals

Abstract

This study presents an irradiation-dependent Internal State Variable (ISV) elastoviscoplasticity-damage constitutive model that accounts for nuclear irradiation hardening and embrittlement of the irradiated polycrystalline materials. The irradiation effects were added to the coupled plasticity-damage kinetics with consideration of the structure-property relationships. The present irradiation-dependent elastoviscoplasticity-damage model was compared to the lab deformation experimental data of irradiated Oxygen-Free High Conductivity (OFHC) copper, Modified 9Cr-1Mo steel, and Ti-5Al-2.5Sn. The results showed excellent agreement over the entire stress-strain curves at various irradiation doses. Because the ISV model, before the irradiation plasticity-damage addition, had been used on over 80 different metal alloys, it is anticipated that this nuclear irradiation supplement will also allow for application to many more irradiated metal alloys.