The Development of UMo/Al Dispersion Fuel

Abstract

UMo/Al dispersion fuel is one of the prospective materials as a high uranium density fuel for high performance research reactors due to its excellent stability during irradiation. In this paper, An overview is provided of current development activities of UMo/Al dispersion fuel at abroad and home, including: the development reasons, this fuel fabrication technology, and the irradiation test. A comprehensive summary is given on the irradiation test, the existing problems and the solution recently obtained by the different countries. Early irradiation experiments with uranium alloys showed promise of acceptable irradiation behavior if these alloys could be maintained in their cubic γ-U crystal structure. The further development of this fuel was delayed due to an unacceptable volume expansion caused by UMo/Al interaction layer (IL) formation and a subsequent gross pore formation at the interface between UMo particles and matrix Al when severe irradiation conditions are reached. In order to alleviate or eliminate the swelling of UMo/Al dispersion fuel,several potential remedies are available to correct the swelling problems. These range from relatively minor changes to the fuel and matrix chemistry, to replacement of the aluminum matrix with another material, or to eliminate the matrix altogether. All of these variations are currently being investigated in the world.