Developments Toward Fully Metallic Actively Cooled Plasma-Facing Components for the Tungsten Divertor in ITER

The evolution toward fully metallic plasma-facing components (PFCs) involves new major challenges in fusion research. For more than 20 years, CEA has focused its experimental studies on actively cooled carbon PFCs. Now, a new step has been taken with the integration of recent technology and physics knowledge for the foreseen implementation of a full-tungsten divertor in Tore Supra (the WEST project) in support of the ITER divertor strategy. To that purpose, various studies dealing with the W environment have been carried out during the past 2 years: analysis of thermal fatigue testing on the latest monoblock designed for ITER divertor targets, including repaired ones; component surface shaping that withstands local particle flux and the effect of leading edges; cumulated transient and steady-state heat loads and their link with the issue of W recrystallization; and acoustic monitoring of the component cooling regimes to prevent critical heat flux events.