Thermo mechanical properties of Mn base binary elements doped UO2 fuel pellets

This paper deals with the fabrication process for Mn base binary elements doped large grained UO2 pellets and their thermo mechanical properties at an elevated temperature of 1450 .deg. C. Two groups of dopant powders were prepared. Small amount of those powder mixtures were added to UO2 powder, which was produced through the ADU process. The powder mixture was pressed into green pellets. The green pellets were sintered in flowing H2. The sintered density and grain size of the doped UO2 pellets were measured and compared. The high temperature thermo mechanical properties were examined by using a compressive creep system under a compressive pressure of 60MPa. This paper reveals that Mn base binary dopant elements can effectively promote a grain growth of UO2 pellets. In addition the high temperature plasticity of the fuel pellets can be improved significantly with an optimum addition of the dopants. Developed Mn-base binary dopants containing UO2 pellets can be potential candidates for a high burn up fuel and a PCI remedy