Understanding Material Dissolution in Aqueous Environments for Fusion Applications

The candidate structural and coolant alloys for the DEMO fusion reactor, such as CuCrZr alloys and reduced activation ferritic/martensitic (RAFM) steels, can exhibit general corrosion when exposed to a flowing aqueous environment, thus promoting the release of metal cations (e.g., Cu, Fe, Cr) into the loop. The formation, release, and redeposition of CPs can strongly affect the structural integrity (e.g., wall thickness reduction) and heat transfer dynamics of the aqueous coolant environment.

Moreover, these corrosion products can become activated corrosion products (ACPs) due to the high-energy neutrons predicted in the plant, thus introducing a radiological hazard to the safety of staff during maintenance operations. The PhD project aims to provide valuable insights to enhance the safety and performance of nuclear power plants by performing cutting-edge characterization of ACPs through microstructural, compositional, and topographical analyses.

The research endeavors to advance knowledge in the field, offering critical information on the impact of ACP formation and mobilization as a function of environmental conditions, deposition rates, and material surface conditions. Methodology and Output:

The PhD project employs a multifaceted methodology that integrates different experimental approaches to quantify the ACP release in an aqueous environment for fusion applications. Experimental investigations will be conducted at the University of Manchester and the Henry Royce Institute, utilizing sophisticated experimental rigs to simulate the environmental conditions predicted in the divertor and breeder blanket components.

The research will focus on the comprehensive characterization of corrosion products, employing microstructural, compositional, and topographical analyses to unravel the complexities of corrosion product formation. The research data will contribute to supporting new and validating existing codes (e.g., OSCAR) to predict the formation of corrosion products in high-temperature, high-pressure water environments specifically for fusion nuclear power plants.