Feasibility study on mass-production of oxide dispersion strengthened Cu alloys for the divertor of DEMO fusion reactor

Oxide dispersion strengthened Cu (ODS Cu) alloys possess a high potential to be used as promising heat sink materials for the divertor system in DEMO fusion reactors. Considering their future application in fusion reactor divertor systems, mass-production of ODS Cu alloys is a must. The purpose of this study is to investigate the feasibility of large-scale production of ODS Cu alloys by improving the production process based on the already established mass-production process of ODS Fe alloys in cooperation with the steel manufacturer Kobelco Research Institute. After optimization of the mechanical alloying (MA) parameters, a large-scale production of ODS Cu powders was successfully achieved with a recovery rate of over 90% and around 1Kg powder in one batch production using an industry-level attritor ball mill cooled by circulating water. The mass-produced ODS Cu alloys were comprehensively characterized, including mechanical properties, microstructure and thermal diffusivity, and a new concept of low-energy ball milling was proposed based on the results to realize the mass-production of ODS Cu alloys.