Direct experimental evidence of melting on a shear band in a molybdenum shaped charge slug

摘要

A "softly recovered" molybdenum shaped charge slug, which shows clear evidence of surface melting in the form of dendrites, on a fortuitously exposed shear band surface, is analysed computationally. The results are compared with a modified form of the critical strain rate condition, derived in the Grady-Asay model (1) of "thermal trapping" which leads to inhomogeneous heating. The comjkputational analysis of the slug formation process indicates that the critical strain rate is exceeded, so that the observed surface melting is consistent with the model prediction.