Patent ID: 6878313
Filing Date: 2005-04-12
Classification: G21C,Y02E

Abstract:
1. A method of fabricating a sintered nuclear fuel compact of uranium dioxide comprising the steps of: providing a starting material that yields a sintered product having an O/U ratio of 1.98 to 2.02 and comprises either: (a) a powder mixture of 75 to 55% by weight of uranium dioxide fresh material powder and 25 to 45% by weight of triuranium octaoxide; or (b) pulverant mixed uranium oxides which may comprise at least one of triuranium octaoxide, tetrauranium nonaoxide, triuranium hexaoxide and uranium trioxide and yield a final stoichiometric O/U ratio substantially equal to that of the powder mixture; two-stage sintering the starting material in an oxidizing atmosphere at a high temperature of from 1200 to 1100° C. in the first stage and a low temperature of no more than 1080° C. in the second stage such that there is at least one temperature rise to the high temperature and at least one temperature drop to the low temperature; and heating the sintered starting material in a reducing atmosphere to produce the sintered product.