Performance of the different tungsten grades under fusion relevant power loads

The test results of several W grades at conditions typical for plasma facing component operations are summarised. These include the effects of steady-state heat fluxes (up to 43 MW/m2), disruption simulation (up to 30 MJ/m2 during 0.05–0.36 ms) and heat flux tests of W after disruption simulation. Representatives of the main W grades have been investigated: pure sintered W, W–Re and W–Mo cast alloys, W–1% La2O3, W–2% CeO2, single crystal W, etc. The resistance to high heat fluxes strongly depends on the orientation of the W grains to incident heat flux and with proper orientation W can withstand heat fluxes up to 27 MW/m2. After disruption simulation, intensive surface crack formation has been observed for all studied W grades except single crystal W. Severe damage after disruption and thermal fatigue loading have been observed for almost all W grades except the W–5Re–0.1ZrC alloy and W–Re single crystal.