| abstract |
The present invention relates to a process for sintering a compacted powder of at least one oxide of a metal selected from an actinide and a lanthanide, this process comprising the following successive steps, carried out in a furnace and under an atmosphere comprising an inert gas, dihydrogen and water:n (a) a temperature increase from an initial temperature T I up to a hold temperature T P , (b) maintaining the temperature at the hold temperature T P , and (c) a temperature decrease from the hold temperature T P down to a final temperature T F , in which the P(H 2 )/P(H 2 O) ratio is such that:n 500<P(H 2 )/P(H 2 O)≤50 000, during step (a), from T I until a first intermediate temperature T i1 between 1000° C. and T P is reached, and P(H 2 )/P(H 2 O)≤500, at least during step (c), from a second intermediate temperature T i2 between T P and 1000° C., until T F is reached. |