Preparation and characterization of (Pu, U, Np, Am, simulated FP) O2−X Original Research Article

The development of low decontaminated mixed oxide (MOX) fuel, which contains minor actinoides (MA) and fission products (FP), is in progress to established Advanced Fast Reactor (FR) Fuel Cycle system. This paper describes the study on the sintering characteristics and the physical properties of MOX fuel containing Am, Np, and simulated FP. MOX powder containing Am, Np and simulated FP were sintered at high temperature in various oxygen partial pressure. From the result of ceramography, it is found that the grain growth rate of the pellets sintered in high oxygen partial pressure is high. From the result of EPMA analysis (Pu, Am, Ln) oxide was observed in the pellets. The melting points of the pellets with oxygen to metal (O/M) ratio of 1.95 are higher than those with O/M ratio of 1.98. This tendency is similar to that of MOX fuel containing about 30% Pu.