Combining AM and FAST for Multi-Functional Refractory Plasma Facing Materials

Extreme particle and heat fluxes within future commercial fusion reactors will exceed 10-20 MW/m2, demanding the most resilient material systems to survive prolonged operation. Materials must tolerate damage from high neutron and charged particle fluxes, and while refractory alloys are promising, sputtering of these materials risks cooling the plasma and disrupting operation. Liquid metals may help address many of these challenges, though maintaining a liquid coating on all surfaces is challenging, requiring resilient solid structures to be manufactured with microscale complexity. Plasma facing components coated in liquid metal (lithium) offer highly desirable properties that can address these issues. To create high-precision microscale structures from resilient refractory- based materials to support a liquid surface through capillary action, two advanced manufacturing technologies will be employed. The approach will combine the advantages of each, including improved thermo-mechanical properties from one and high precision small scale features of the other, resulting in a resilient, reliable porous plasma facing material to support a liquid interface with the plasma. Phase I will address critical questions around the feasibility of merging these technologies, including microstructure and material properties, manufacturing precision and scale, and post-processing cleaning. Phase II will develop scaled production and test performance of the material with liquid metals under extreme conditions. Fusion is an abundant, affordable, and clean energy source will help to avoid climate disaster in the long run and ensure energy security. This project will not only enable liquid metal plasma facing components in appropriate fusion reactor designs, but also address complex components in reactors with solid components that face machining challenges with brittle materials. Tailored interfaces between solid and liquid metals at high temperatures have several other potential applications, such as thermal management systems in hypersonic vehicles.