Thermomechanical Instability Analysis of Inhomogeneous Deformation in Amorphous Alloys

Abstract

Recent experiments have shown that inhomogeneous deformation in amorphous alloys critically depends on the environmental temperature and the applied strain rate, and the temperature field inside the shear band can rise up to the glass transition temperature. A thermo-viscoplastic constitutive law is developed that accounts both stress-driven and thermally induced strain softening behavior. A perturbation analysis is carried out to examine the conditions for unstable temperature growth. A deformation mechanism map is constructed and compared to the available experiments.