Study of radioactive inventory generated from W-based components in ITER and PPCS fusion designs

Highlights: ► Recycling and clearance would be a potential solution to reduce the radioactive inventory. ► Both ITER and PPCS divertors ultimately classify MA-VL according to French regulations. ► The most attractive alloys appear to be W–1%Ta, W–TiC, W–K and W–La2O3. ► W transmutation strongly depends on the neutron spectrum and fluence. -- Abstract: Tungsten and its alloys are currently considered as prime candidates for plasma facing components in many fusion experimental devices and power plants, but some issues regarding the activation of these materials remain to be clarified. This study has addressed the activation concerns of seven candidate W-alloys (W–W composites, W–La2O3, W–TiC, W–Ta, W–K, VM tungsten and W–Re) that could be used for W-based divertors and W-armors under the operating conditions of the ITER experimental facility and the PPCS power plant (EU power plant design studies). More specifically, the three radioactive waste management options (disposal, recycling, and clearance) as well as the transmutation of W have been examined. The latter is quite sensitive to the divertor and blanket materials. About 5–8 at.% of the W-armor transmute at the end of the PPCS blanket lifetime while the transmutation in the W-based divertor is <1%. Such a low transmutation level may not impair the physical properties of divertor W-alloys