Fusion-dedicated material irradiation facilities at MYRRHA: Conceptual design and damage equivalence studies

The Belgian Nuclear Research Centre is currently developing MYRRHA - a subcritical accelerator driven system ignited by a 600 MeV superconducting linear proton accelerator, cooled with an eutectic lead bismuth. The implementation of MYRRHA will take place in phases, where phase I, covering 2019–2027, includes the deployment of the 100 MeV proton accelerator and beam-added research facilities. Development of the dedicated facilities to enable irradiation of fusion materials and components is in the portfolio of this R&D block. The baseline concept of the 100 MeV fusion-dedicated facilities has been presented for the first time in 2019 and in this contribution, we extend its description and provide main elements of the conceptual design of the irradiation installations, preliminary configuration of the hot cell facilities (required to load/unload the irradiation modules), information on the irradiation envelope. In addition, we summarize the results of the computational study performed to investigate the equivalence (in terms of damage rate, nuclear transmutation, temperatures and expected irradiation-induced microstructure) of the irradiation conditions at MYRRHA facilities in comparison with other material test facilities such as IFMIF and ESS, and in DEMO as well as in the mixed-spectrum material test reactors. The aspects related to miniaturization of the sample geometries are also discussed to substantiate the feasibility and relevance of this facility for fusion material’s R&D programme.