One daunting challenge facing future plasma burning fusion reactors is the extreme conditions that expose plasma-facing components (wall materials) are exposed to. Extreme particle and heat fluxes exceeding 10-20 MW/m2 drive traditional material surfaces out of equilibrium and induce topographical and compositional changes that can have deleterious effects on the plasma edge and, ultimately, the confinement of fusion plasma. Processing of refractory alloys has been challenging and it is uncertain if solid plasma facing components are a viable option for future fusion reactors. Plasma facing components coated in robust liquid metal (tin, tin-lithium) systems offer highly desirable properties that can address these issues. This work will utilize a research fusion reactor and unique diagnostic tool to develop and test the performance of experimental refractory metal materials coated with static and dynamic liquid metal coatings within the experimental fusion environment. Phase 1 work will consist of performing the feasibility studies to develop robust liquid-metal PFC solutions by leveraging the small-scale HIDRA device as a validation platform for harnessing advanced mesoporous refractory-metal scaffolds. This work will quantify performance in terms of hydrogen and helium retention, impurity segregation, glow discharge cleaning, and surface wetting. The potential markets that exist for these technologies are vast. The proposed program is aimed at delivering a critical enabling technology for the development of fusion reactors: A high-temperature radiation-resistant material for PFCs. We anticipate that using the mesoporous W substrates will be the basis for W-based PFCs that could lead to significant advancement in the development of high-heat flux component materials for future plasma-burning fusion reactor devices designed to produce energy. Beyond nuclear fusion, the proposed refractory alloy nanocomposites promise to impact industries where materials are exposed to extreme conditions of pressure, heat, and radiation including: IC (internal combustion) engines, solar power towers, nuclear fission power reactors, and gas cooled fast reactors.
