Dynamic compression failure of two metals at 0.5 and 1.5 GPa

The influence of pressure on dynamic failure under compression of a high-strength tungsten alloy and a hardening steel was investigated. Two dynamic compression tests were employed. The first one, a symmetric Taylor test, provides low pressure data while the second one, a modified version of the hat test called the hydrodynamic hat test, generates data at pressures up to 1.5 GPa. Failure strain data were obtained from numerical simulations of the tests. For both metals, the increase of pressure was found to lower the failure strain associated with adiabatic shear banding preceding shear failure. These results are interpreted through a reduction of the plastic work being converted in heat with the increase of pressure delaying adiabatic shear band formation.