Materials Response to Large Plastic Deformation

Abstract

Many important practical applications of metals require a knowledge of the plastic response at large deformations and at high strain rates. For example, metal forming processes and impact or penetration problems combine the effects of large strain, high rate and temperature. Accurate modeling of such processes requires a good constitutive description of material behavior. However, controlled laboratory experiments at large strains are difficult because most involve large geometry changes accompanied by either deformation gradients (such as barreling in compression) or plastic instability (such as necking in tension). High rate deformation adds the complication of an uncontrolled temperature rise. In the strain rate regime of 1 to 103sec-1, deformation may be neither completely isothermal nor adiabatic, but a combination.