Developing and Evaluating Candidate Materials for Generation IV Supercritical Water Reactors

Gary Was


1921 Cooley

T: (734) 763-4675






The goal of this project is to establish candidate materials for supercritical water reactor designs and to initiate the evaluation of the mechanical properties, dimensional stability, and corrosion resistance. To overcome the principal technical and scientific obstacles to the long-term future use of nuclear energy, new reactor designs must offer enhanced safety and reliability, sustainability and economics. To meet these goals, Generation IV (GEN IV) reactor designs must incorporate advanced materials for cladding and structural components. Currently, insufficient physical property data exist to qualify candidate materials. In many cases, candidate materials have not even been identified. For all Generation IV designs, significant materials property data must be obtained to license future reactor designs. To meet the goals of the GEN IV Reactor research initiative, international collaborations are critical in terms of shared resources and shared expertise. Because of the significant costs associated with nuclear systems research an international cost sharing approach will provide maximum value for the limited research dollars. Both the Republic of Korea (ROK) and the United States (US) have a shared interest in the development of advanced reactor systems that employ supercritical water as a coolant.Supercritical water reactors (SCWR) are one of the more promising Generation IV nuclear systems concepts due to enhanced thermal efficiencies and relative compactness when compared to current light water reactor (LWR) technology. The relatively mature alloy development programs for supercritical fossil plants (SC-FP) can be used as a baseline for the development of fuel cladding and structural materials in a SCWR. The SC-FP alloys have known corrosion resistance properties but have not been evaluated relative to degradation in radiation fields. Additionally, materials developed for the fast reactor programs, which operated in similar temperature regimes as SCWR, will also be evaluated for SCWR applications. These alloys have known radiation resistance, but the corrosion performance is unknown. To understand the relative materials compatibility, a comprehensive research program is proposed that initially evaluates state-of-the-art SC-FP and fast reactor materials for application in SCWR, and expands on these alloys to produce materials optimized for SCWR fuel cladding and core internal structures.