Metallographic examination of an irradiated powder metal uranium slug from PT-313-105-4M⁽¹⁾ was undertaken primarily as an evaluation of recently remotized metallographic equipment. It was, also, proposed to compare the grain size with values obtained ultrasonically on the same slug. It was further proposed to make a comparison, so far as limited data permitted, of post-irradiated powder metal uranium grain size with that to be expected from normal uranium similarly irradiated.

This report discusses preliminary results acquired from investigations made on the ultrasonic properties of uranium, such as sonic vibrations in the megacycle frequency range.