Isentropes of relief of iron and austenitic steel from the state of shock compression at a pressure of 150 GPa

The results of experiments in isentropic expansion of iron and austenitic s teel from the state of shock compression in the pressure range from 120 to 200 GPa are used to determine the isentropes corresponding to melting at no rmal pressure. The position of the latter isentropes on the phase diagrams is analyzed on the basis of comparison with the available experimental and theoretical data for solid phases of iron at high pressures and temperature s.