Abstract and subjects
The uranium-silicon binary system possesses a range of compounds that have been historically investigated and utilized to a limited extent as nuclear reactor fuels. Of the multiple compounds, U sub(3)Si and U sub(3)Si sub(2) are most familiar; their high uranium densities have made them an intriguing choice for incorporation into composite plate fuels in research reactors and other low power core redesigns where retained neutronic performance was desired at lower enrichments [1], This increased uranium density compared with uranium dioxide (UO sub(2)) has made them attractive to a new generation of nuclear fuels research driven by the renewed push for accident-tolerant light water reactor (LWR) fuels. A higher uranium density may motivate incorporation of U-Si phases into composite fuels that utilize secondary phases with the goal of increasing coping time during a cladding breach before fission products and/or actinides are released. Additionally, development of fuels containing higher uranium densities than those of reference UO sub(2) could facilitate utilization of alternative cladding materials that offer improved high temperature performance than zirconium alloys but incur neutronic penalties.