MODELING OF HARDENING AT VERY HIGH-STRAIN RATES

A modification of the Bodner-Partom elastic-viscoplastic constitutive model is proposed to account for strain rate dependence of the evoluti on of hardening. The suggested procedure is for the rate of hardening in the hardening evolution equation to be a direct function of total s train rate. Material constants are determined for oxygen-free-electron ic copper and simulations of response behavior at very high rates of s training appear to be consistent with test observations.