Combinatorial Modeling, Screening and Development of Tungsten- Ceramic Composites with Gradient Microstructure for Improved Radiation-Tolerant Plasma Facing Materials

ARPA-E Concept Paper DE-FOA-0003240 Title: COMBINATORIAL SCREENING AND DEVELOPMENT OF GRADIENT-POROSITY TUNGSTEN FOR RADIATION-TOLERANT PLASMA FACING MATERIAL PI: Thomas John Balk Abstract: The proposed concept addresses the Program Objectives of DE-FOA-0003240 by outlining a combinatorial approach to identify candidate material phases for the design and development of a new composite material (tungsten-based alloy with porosity gradient and back?lled with ceramic) that will meet the performance metrics speci?ed for plasma-facing materials in a reactor chamber. Our team will leverage background experience in porous tungsten-based systems with complex microstructure, which are used in the dispenser cathode community, and which were the focus of a recent DARPA INVEST project where the PI was a performer. The overall material system will be based on porous tungsten, due to the ability of small-scale grains and ligaments to tolerate irradiation via di?usion of radiation-induced defects to pore surfaces, which act as a sink for these defects. Back?lling with ceramic will create material interfaces that service as sinks for radiation damage, while also promoting thermal conductivity via selection of appropriate ceramic(s) to not only mitigate the typical drop in thermal conductivity for porous materials, but actually increase the overall thermal performance. The overall goal is to identify candidate composite materials with the most promising properties to meet performance metrics.