Grant: NSERC/NRCan/AECL Generation IV Energy Technologies Program

Concerns with green house gas emissions and uncertainty in the long-term supply of fossil fuels have resultedin renewed interest in nuclear energy as an essential part of the energy mix for the future. Currently, there is aworldwide effort to develop advanced Generation-IV nuclear reactor technologies with enhanced efficienciesand reduced operating cost. Canada is playing a lead role in the design of the Supercritical Water-CooledReactor (SCWR) - one of six reactor designs being considered by the Gen-IV International Forum (GIF). TheSCWR design will use supercritical water as coolant in order to achieve high thermodynamic efficiency (i.e.,over 45% vs. 33% for current reactors) and plant simplification. One of the major challenges for thedevelopment of the SCWR is the long-term stability of the materials in contact with the coolant. In thisresearch, the effect of long term exposure in super-critical water (500- 850°C) on corrosion behaviour,microstructure, and mechanical properties of coated and uncoated candidate substrate alloy(s) for use in aSCWR will be examined. FeCrAlY or NiCrAlY based plasma spray coating and aluminide based diffusioncoating processes (all developed in phase one of the program) will be employed to provide improvement to thecorrosion resistance and microstructure stability of the selected substrate alloy. After SCW exposure, thecorrosion behaviour and microstructure changes will be analyzed. For the most promising coating andsubstrate system in terms of corrosion resistance and microstructure stability, high temperature mechanicalproperty tests will be carried out to elucidate what influence the coating may have on the mechanical integrityof the structural components for SCWR. The new knowledge and expertise generated from this research willhelp strengthen Canada's nuclear industry, particularly in the development and commercialization of SCWR.This research will help fulfil Canada's commitments to the SCWR Materials and Chemistry ProjectArrangement under the Framework Agreement for International Collaboration on Research and Developmentof Gen IV Nuclear Energy Systems.