Abstract
The theory of solid-phase sintering and its experimental investigation are reviewed. Uranium-plutonium carbonitride powders were prepared by carbothermic reduction and their sintering kinetics studied by dilatometry using a constant-rate-of-heating and Dorn method. The influence of a pre-sintering hydrogen treatment was investigated. The difference in the apparent activation energy of sintering determined by the two methods and the change in kinetics caused by the hydrogen treatment are explained with reference to the diffusion characteristics of carbonitrides.