Technology readiness assessment of materials for DEMO in-vessel applications

Abstract

A dedicated procedure was developed to categorize the technology readiness of materials for specific DEMO in-vessel fusion reactor applications. This methodology was employed to assess the technological maturity of materials under development within the EUROfusion materials work package (WPMAT). This covers materials intended for structural, high heat flux, optical and dielectric applications in the European DEMO fusion reactor (breeder materials and barrier coatings are not covered here). The baseline materials have been assigned DEMO Material Technology Readiness Levels (MTRLs) of 4 (EUROFER97), 3 (conventional tungsten) and 4 (Copper-Chromium-Zirconium). In addition, a further 28 candidate materials (and groups of materials) were also assessed. These were generally assigned DEMO MTRLs in the range of 2-3. This process has highlighted the wide range of materials under development within WPMAT. However, it has also brought into focus the many challenges facing DEMO materials development. While the lack of technologically ready materials is clearly a source of risk to DEMO, the introduction of a biennial review of technology readiness within WPMAT is intended to facilitate more effective planning and targeted materials development, in line with the strategic plans of EUROfusion. This paper highlights the methodologies for fusion specific material technology readiness levels, their application for EU-DEMO and the effectiveness of these in strategic materials development.