Fabrication and characterization of americium, neptunium and curium bearing MOX fuels obtained by powder metallurgy process

MOX fuel pellets containing up to 1.4 wt% of Minor Actinides (MA), i.e. Am, Np and Cm, were fabricated to demonstrate the technical feasibility of powder metallurgy process involving, pelletizing and sintering in controlled atmosphere. The compounds were then characterized using XRD, SEM and EDX/EPMA. Dense pellets were obtained which closed porosity mean size is equal to 7 μm. The results indicate the formation of (U, Pu)O2 solid solution. However, microstructure contains some isolated UO2 grains. The distribution of Am and Cm appears to be homogeneous whereas Np was found to be clustered at some locations.