The adoption of nuclear fusion as a practical energy source is limited by the availability of materials which can withstand the extreme environment experienced by plasma-facing components. Materials development can be significantly accelerated by using computational materials modelling tools, capable of predicting the microstructure evolution during processing and service, and its effects on the properties of the materials. This is especially relevant in fusion applications in which components will be at high temperatures for significant periods of time, and therefore are innately difficult to replicate experimentally.

This study presents a model for the precipitation kinetics in CuCrZr alloys, which are utilised as potential heat sink material for divertor target designs. A multi-class Kampmann Wagner numerical modelling framework was used to describe the evolution of the precipitate size distribution. The model was calibrated with time-dependent precipitation data and further tested against different experimental data to establish a temperature dependence of the main parameters.

The calibrated model was then used to predict the long-term coarsening behaviour of coherent fcc chromium precipitates, specifically how the alloy microstructure evolves when at working temperatures and time scales relevant to fusion materials.