European structural materials development for fusion applications

Leading long term considerations for choices in the European Long Term Tech nology programme are the high temperature mechanical- and compatibility pro perties of structural materials under neutron irradiation. The degrees of f abrication process freedom are closely investigated to allow the constructi on of complex shapes. Another important consideration is the activation beh aviour of the structural material. The ideal solution is the recycling of t he structural materials after a relatively short 'cooling' period. The stru ctural materials development in Europe has three streams. The first serves the design and construction of ITER and is closely connected to the choice made: water cooled austenitic stainless steel. The second development strea m is to support the design and construction of DEMO relevant blanket module s to be tested in ITER. The helium cooled pebble bed and the water cooled l iquid lithium concept rely both on RAFM steel. The goal of the third stream is to investigate the potential of advanced materials for fusion power rea ctors beyond DEMO. The major contending materials: SiCSiC composites, vanad ium, titanium and chromium alloys hold the promise of high operating temper atures, but RAFM has also a high temperature potential applying oxide dispe rsion strengthening. The development of materials for fusion power applicat ion requires a high flux 14MeV neutron source to simulate the fusion power environment. (C) 2000 Elsevier Science S.A. All rights reserved.