The impact of low-activation criteria on the development of novel materials for fusion

The utilisation of low-activation materials (LAMs) has been recommended in the Report of the \CEC\ Fusion Evaluation Board (“Colombo Report”) as a mean to demonstrate the safety and environmental feasibility of fusion. On this basis, criteria for the choice and the development of \LAMs\ are proposed. They are based on the compliance to short- and long-term radioactivity limits and relate to accidental situations, maintenance and waste management. The relative importance, or ranking, of each criterion is adjusted to the peculiar properties and requirements of each reactor component. Activation levels of typical constituting materials are evaluated for each component and compared with the relevant criteria. Materials composition data for the development of novel \LAMs\ are defined. Low activation reference tables are also presented.