Material research for small modular reactor cooled by supercritical water – ECC-SMART

Abstract

The main objectives of the project are to define the design requirements for the future SCW-SMR technology, to develop the pre-licensing study and guidelines for the demonstration of the safety in the further development stages of the SCW-SMR concept including the methodologies and tools to be used and to identify the key obstacles for the future SMR licencing and propose strategy for this process. The project consortium consists of laboratories from Europe, Canada and China. Beside the thermo-hydraulics, safety, neutronics, and reactor physics, assessment of the corrosion behaviour of cladding candidate materials (alloy 800H, stainless steel 310S, alumina forming austenitic alloy -AFA) in supercritical water (SCW) at 380/500 °C and 25 MPa is one of the key activities. For this purpose, experiments such as long-term (1000-8000 hours) exposure tests in autoclaves, neutron irradiation, electrochemistry, and radiolysis are involved. The paper describes the progress made on the ECC-SMART project with focus on microstructural characterization of candidate cladding materials. In addition, the description of the setup of corresponding experiments is included.