Isentropic compression of irradiated stainless steel on the Z accelerator

摘要

We have performed quasi-isentropic compression experiments on radiation-damaged stainless steel. The samples were dynamically loaded by Sandia National Laboratory's Z accelerator with a ramp compression wave. Sample/window interface velocities were recorded with VISAR. The velocity histories suggest a sudden volume reduction of the material above 40 kbar caused by the collapse of nanosized voids. This is predicted by a theoretical model of void collapse based on the emission of vacancy-type dislocations loops. We compare the results of these experiments to hydrodynamic calculations performed using a constitutive model which is derived from the atomistic void collapse mechanism.