1 Self passivating W-based alloys as plasma facing material

Self passivating tungsten-based alloys may provide a major safety advantage in comparison with pure tungsten (W) which is presently the main candidate material for the plasma-facing protection of future fusion power reac-tors. Films of binary and ternary tungsten alloys were synthesised by magnetron sputtering. The oxidation behav-iour was measured with a thermobalance set-up under synthetic air at temperatures up to 1273 K. Binary alloys of W-Si showed good self-passivation properties by forming a SiO2 film at the surface. Using the ternary alloys W-Si-Cr, W-Si-Y, and W-Si-Zr the oxidation behaviour could be further improved