Adiabatic shear bands in the Taylor impact test for a WHA rod

We analyse the development of shear bands in axisymmetric, thermomechanical deformations of a circular tungsten heavy alloy (WHA) rod impacting at nor mal incidence a smooth rigid target. The rod's material is modeled either a s a mixture of Fe-Ni-W particles interspread randomly among the W-particles or as a homogeneous alloy. For comparison purposes we also analyse deforma tions of a pure W and an Fe-Ni-W rod. It is found that shear bands, defined as narrow regions of rapid intense plastic deformation, form near the tran sition between the mushroomed region and the relatively undeformed portion of the rod, when its material is either a mixture of Fe-Ni-W and W particle s or a homogeneous alloy but no such bands form in rods made of either W or Fe-Ni-W only. This could be due to the different initial softening rates o f the materials. (C) 1998 Elsevier Science Ltd. All rights reserved.