Development of high density uranium compounds and alloys as dispersion fuel for research and test reactors

Most of the research and test reactors worldwide have undergone core conversion from high enriched uranium base fuel to low enriched uranium base fuel under the Reduced Enrichment for Research and Test Reactor (RERTR) programme, which was launched in the late 70’s to reduce the threat of nuclear proliferation. Various compounds of uranium were considered and studied for the purpose but the best fuel compound identified for the development of low enriched uranium base fuel was uranium silicide (U3Si2). The fabrication method qualified for making U3Si2-Al dispersion fuel was giving a maximum heavy atom density in the range of 4.8 g/cm3 to 6.0 g/cm3. Under the RERTR programme an ambitious goal of achieving heavy metal density of 8.0 to 9.0 g/cm3 in aluminium based dispersion fuel was set and to realize this high density γ - stabilized uranium alloy (e.g. U-Mo, U-Zr etc.) powder in conjunction with advanced fabrication techniques.