Densification behaviour and sintering kinetics of PuO2 pellets

The sintering behaviour of PuO2 pellets has been studied using a dilatometer in inert, reducing and oxidising atmospheres. The shrinkage rate was found to be maximum for pellets sintered in Ar–8% H2 atmosphere. The mechanism for the initial stage of sintering was determined using rate controlled sintering (RCS) technique and was found to be volume diffusion for both inert and reducing atmospheres. The activation energy for the initial stages of sintering was found to be 210 and 159 kJ/mol for Ar and Ar–8% H2 atmospheres, respectively. The mechanism for the sintering in oxidising atmospheres could not be evaluated using RCS technique.