THERMOPHYSICAL PROPERTIES OF

Abstract

Thermochemical and thermophysical determinations have been performed on UN, PuN, and U//0. //8Pu//0. //2N. For the most part it has been established that the properties of U//0. //8Pu//0. //2N are intermediate between that of UN and PuN. Heat capacity seems to be a near-linear function of composition and the thermochemical determinations indicate that UN and PuN form a near ideal solution. The ideal solution concept does not apply to the individual elements plutonium and uranium, however. The metal/ nitrogen ratio seems governed by the plutonium while mass transport is governed predominantly by diffusion of plutonium through a surface layer of uranium nitride.