W-Based Alloys for Advanced Divertor Designs: Options and Environmental Impact of State-of-the-Art Alloys

The development of radiation-resistant materials to sustain the harsh fusion environment represents a challenging task for divertor designers. In recent years, advanced physics simulations of the power leaving the plasma with radiation and charged particles indicate much higher heat fluxes to the divertor than previous estimates. In response, experts in EU, Japan, and US developed several W alloys for advanced He-cooled divertors that can handle heat fluxes in excess of 10 MW/m². This paper briefly discusses the ongoing effort to develop W alloys suitable for fusion applications, the challenging phenomena impacting the behavior of W under a fusion environment, and the environmental impact of the most promising, state-of-the-art alloys: W-La₂O₃ and W-1.1TiC.