Phase Relations in Crystalline Ceramic Nuclear Waste Forms the System UO/sub 2 + X/-CeO sub 2 -ZrO sub 2 -ThO sub 2 at 1200 exp 0 C in Air

摘要

Steady-state phase relations in the system UO/sub 2 + x/-CeO sub 2 -ZrO sub 2 -ThO sub 2 were determined for application to phase relations in the high-level crystalline ceramic nuclear waste form Supercalcine-Ceramics. Samples were treated at 1200 exp 0 C at an oxygen partial pressure of 0.21 atm and a total pressure of 1 atm. Phase assemblages were found to be composed of cubic solid solutions of the flourite structure type, solid solutions based on ZrO sub 2 , and orthorhombic solid solutions based on U sub 3 O sub 8 . (ERA citation 06:012593)