Development of Novel Mesoporous Substrates for a Stable Liquid-metal Plasma-material Interface under Ultra Long-pulse Plasmas

One daunting challenge facing future plasma burning fusion reactors is the extreme conditions that plasma facing components 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 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 II work will optimize mesoporous refractory scaffolding material to support the liquid metal interface. This work will establish how fuel will be managed, specifically hydrogen and helium retention and impurity segregation. This will be utilized to design a compact steady state/long-pulse device that can be constructed more affordably and on a shorter timeline (10-15 years) than current designs (ITER, DEMO). Commercial Applications and Other Benefits: The program is aimed at delivering a critical enabling technology for the development of fusion reactors: A high-temperature radiation-resistant material for plasma facing components (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 fusion reactor devices designed to produce energy. Beyond nuclear fusion, the proposed refractory alloy nanocomposites may 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.