Understanding and anticipating material degradation in extreme environment : from alloy design to fundamental mechanisms

One of the most decisive factors in the rapid deployment of advanced nuclear reactors, whether fission or fusion, with major gains in safety and efficiency, is undoubtedly the development and qualification of irradiation- and corrosion-resistant materials, which form the structural components and first barriers of reactor cores. However, the discovery, improvement and evaluation of such materials in the extreme environments of these reactors are demanding, time-consuming and costly processes, severely hampering the innovation and qualification of materials for nuclear power. This seminar highlights research into the irradiation and corrosion of compositionally complex alloys (CCAs) for structural components, fuel cladding and walls exposed to plasma. The “top-down” approach adopted is based on two components.

(i)     an integrated high-throughput research platform combining alloy development, testing and characterization to explore vast spaces of compositions;
(ii)     targeted, finely-controlled experiments, coupled with atomic-scale modeling and characterization, to reveal degradation mechanisms.
This “top-down” approach enables us to understand the fundamental degradation mechanisms and develop predictive models, based on machine learning, to anticipate the behavior of CCAs under high-dose irradiation and molten-salt corrosion conditions. The ultimate goal is to accelerate the discovery of new materials for advanced nuclear reactors, both fission and fusion.