Phase transition and spall behavior in β-TiN

We have undertaken a study of Sn in an effort to understand the spall and phase transition behavior of this material. The initial results, obtained with tin having 1–2% impurities, show the phase transformation from the β to the γ phase during the shock event with kinetic effects evident. Preliminary modeling suggests that the reverse transition occurs somewhat more rapidly than the forward transition. Records of the experimental free surface velocity show a signal usually considered indicative of spall, but analysis of a recovered sample calls that interpretation into question for the lower-pressure experiments. At higher shock pressures, flash x-ray images of the samples confirm that the samples did spall as expected.