Determination of the defect creation mechanism in fluoroapatite

Most of strategies to immobilize actinides are concerned with their incorporation in dedicated solid matrices for a long disposal-time. Chemical durability of these matrices is a major problem. Radiation damages due to α-decay events can strongly reduced it. The defect creation mechanism has been determined in fluoroapatite using a transmission electron microscope (TEM) on line with an ion implanter. At room temperature, the defect creation is controlled by amorphization directly in the cascade. From this result and published data on the defect annealing in this material, the disorder evolution as a function of time has been established. An application concerning the incorporation of 244Cm is considered.