Recent advances in the development of SiC/SiC as a fusion structural material

Silicon carbide composites are attractive for structural applications in fusion energy systems because of their low activation and afterheat characteristics coupled with their excellent high-temperature properties. These new materials will require optimization of their hermeticity, thermal conductivity, radiation stability, chemical compatibility with fusion relevant environments, and joining methodology before they can be utilized effectively in a fusion energy system. Recent advances have been demonstrated for advanced SiC fibers and fiber/matrix interfaces. Improved creep resistance and radiation stability have been demonstrated for Hi-Nicalon, Nicalon-S and DOW/Corning Sylramic fibers. Advanced fiber/matrix interfaces made with porous SiC and multi-layer SiC/C/SiC are being developed to minimize the presence of C in the interface for improved radiation and chemical stability of the composite materials. There have also been advances in evaluating He effects in SiC/SiC composites, the effects of 26Al on activation of SiC and joining methodology for SiC/SiC composites. These advances continue to support the promise of these advanced composite materials for fusion energy applications.