DENSITY‐DEPENDENT ACOUSTIC PROPERTIES OF PBX 9502

We have measured the longitudinal and shear acoustic velocities of PBX 9502 as a function of density for die‐pressed samples over the range 1.795 g/cc to 1.888 g/cc. The density dependence of the velocities is linear. Thermal cycling of PBX 9502 is known to induce irreversible volume growth. We have measured the density dependence of the volume growth for a subset of the pressed parts and find that the most growth occurs for the samples with lowest initial density. The acoustic velocity changes due to the volume growth are significant and reflect damage in the samples.