STEADY-STATE SMEAR BAND PROPAGATION UNDER DYNAMIC CONDITIONS

The dynamic propagation of a shear band is assessed in mode II. A laye r of finite thickness is subjected to simple shearing.:The band propag ates in the shear direction under steady state conditions. Three param eters are used to characterize the process: the shear band velocity, t he length of the process zone and the width of the sheer band. The pro cess zone is the region at the vicinity of the shear band tip where th e strain rate changes rapidly from a quasi-uniform profile to a locali zed distribution. The shear band velocity and the length of the proces s zone are calculated by use of a variational approach. We analyse the roles of inertia, of loading conditions and of material properties su ch as yield stress, strain (or thermal) softening, strain hardening, s train rate sensitivity. The effect of elastic energy release is shown to be important in general. Comparisons with experimental results are made. (C) 1998 Elsevier Science Ltd. All rights reserved.