Nanostructured Tungsten for Improved Plasma Facing Component Performance

70508B02-II To reduce the cost of burning-plasma experiments conducted for fusion energy research, refractory metals are required to increase high heat flux limitations for plasma facing component applications. For refractory metals such as tungsten (W) to be used in fusion applications, improvements in both mechanical and physical properties are needed. Because recent work identified the benefits of nanosize, transition-metal-carbide dispersoids within tungsten, this project will develop fabrication techniques to enable the near net shape forming of nanograined W and W alloys, with improved resistance to embrittlement, for use in fusion reactors. Phase I demonstrated the feasibility of producing near net shape W components comprised of ultra-fine grained microstructures. Analyses of the samples showed that tungsten materials reinforced with transition metal carbide have a higher recrystallization temperature, experience less grain growth at elevated temperatures, and have higher hardness values than pure tungsten samples. During Phase II, techniques developed during Phase I will be optimized and used to fabricate extensive material property specimens. Rhenium additions will be evaluated to further improve ductility. Finally, plasma facing component mockups will be fabricated to demonstrate the scalability of the process. Commercial Applications and Other Benefits as described by awardee: Potential commercial applications include, but are not limited to: ballistic and tactical missiles, gun barrel liners, arc-jet thrusters, heat exchangers, welding electrodes, plasma facing components for nuclear reactors, integral oxidation protection for burners, gas turbines, automobile engines, incinerators, thermal control coatings, oxidation protective coatings, coatings for composite parts and structures, thermal barrier coatings, structural jackets on tubular combustors and nozzles, and storage vessels.