Sodium Compatibility of Advanced Fast Reactor Materials

Advanced materials have been identified as one means of improving reactor performance via increased safety margins, design flexibility, and fast reactor economics. Increased strength and creep resistance can give greater design limits leading to improved safety margins, longer lifetimes, and higher operating temperatures, thus enabling greater flexibility. Improved mechanical performance may also help reduce the plant capital cost both by reducing the required commodities (with concomitant reductions in welding, quality assurance and fabrication costs) and through design simplifications. Alloys such as NF616, HT-UPS, and ODS steels offer revolutionary gains in high-temperature performance and hence, reactor performance over traditional materials such as HT9 and 316SS. However, while these materials have been used in other industries and have proven improvements in strength, there is very little information on their compatibility in a liquid metal coolant. The objective of this effort is to provide an initial assessment of sodium corrosion compatibility of the improved materials being considered for advanced fast reactor applications. In addition, this work will also provide valuable insight into licensing and regulation issues associated with materials compatibility (such as coolant impurity limits) that were raised during evaluation of the Clinch River Breeder Reactor and initial reviews of the PRISM design. This FWP is related to a proposal that is being submitted in response to DOE Solicitation DE-PS07-08ID14906 entitled "2008 Advanced Fuel Cycle Research and Development". Program Element Area - Fast Burner and Advanced Transumtation Systems