Corrosion and Environmental Degradation of Materials in High Temperature Small Modular Reactor Environments

小型模块化反应堆（SMR）是一种非常低碳的核能来源，可以解决全球气候变化问题。加拿大政府已经认识到这一点，并制定了成为SMR技术开发领导者的计划，以最大限度地提高经济，能源和环境效益。然而，SMR部署的关键技术障碍是许多设计中存在的腐蚀性环境的材料选择。例如，熔融氯化物盐和高温氦被提议用于计划在2030年之前在加拿大的SMR原型的冷却剂。在这些SMR中材料的腐蚀是不清楚的，特别是辐射场和腐蚀性环境的组合效应。加拿大核安全委员会（CNSC）将需要解决这一知识差距，以提供风险知情的监管监督，并制定代码，特别是SMR中的材料选择和化学控制。因此，该项目将研究材料在熔盐和高温气体环境中的性能，以开发新材料，为化学控制提供信息，指导监管机构的政策和决策，并确保在加拿大安全有效地部署SMR。为了在这些极端环境中进行研究，我们的多学科专家团队将采用新颖的实验方法，包括用于高温气体和熔盐测试的独特腐蚀设施，用于辐照材料的质子加速器技术以及新颖的显微镜技术。该研究旨在系统地研究SMR中材料降解的重要变量，以建立可以为监管政策提供信息的边界条件，包括：辐射剂量，温度，杂质含量和材料成分。 此外，该项目将解决SMR环境中腐蚀的科学差距，包括辐射效应，并为高素质人员（HQP）提供前沿培训。HQP在SMR技术方面拥有世界领先的知识，可以保持和提高加拿大SMR的研究和工程能力，保持该国作为核能世界领导者的声誉。

Small modular reactors (SMRs) are a very-low-carbon nuclear energy source that can address world-wide climate change concerns. The Canadian government has recognized this, and established initiatives to be a leader in development of SMR technology to maximize significant economic, energy, and environmental benefits. However, the key technological obstacle to SMR deployment is materials selection for the corrosive environments present in many designs. For example, molten chloride salts and high temperature helium are proposed coolants for SMR prototypes planned in Canada by 2030. The corrosion of materials in these SMRs is unclear, especially the combined effect of radiation fields and the corrosive environment. The Canadian Nuclear Safety Commission (CNSC) will need to address this knowledge gap to provide risk-informed regulatory oversight, and for code development, specifically for materials selection and chemistry control in SMRs. Thus, this project will study materials performance in molten salt and high temperature gas environments to develop new materials, inform chemistry control, guide regulator policy and decision-making, and ensure the safe and effective deployment of SMRs in Canada. To perform research in these extreme environments our team of multi-disciplinary experts will apply novel experimental methods, including unique corrosion facilities for high temperature gas and molten salt testing, proton accelerator technology for irradiating materials, and novel microscopy techniques. The research aims to systematically study important variables for materials degradation in SMRs to establish boundary conditions which can inform regulator policy, including: radiation dose, temperature, impurity content, and material composition. Furthermore, this project will address scientific gaps for corrosion in SMR environments, including radiation effects, and provide leading-edge training for highly qualified personnel (HQP). Development of HQP with world-leading knowledge in SMR technology allows for retaining and increasing research and engineering capacity for SMRs in Canada, maintaining the country's reputation as a world leader in nuclear energy.