Recent progress of SiC-fibers and SiC/SiC-composites for fusion applications

Recent progress in R and D of SiC fibers and reinforced SiC matrix (SiC/SiC) composites in Japan, especially focusing on the activities of CREST-ACE program, is presented. Firstly, the present status of high performance SiC fiber development, such as Hi-Nicalon Type-S and Tyrano-SA, is provided. The high performance SiC matrix production by reaction sintering (RS) method improved in both strength and thermal conductivity are accomplished. The efforts to make appropriate fiber-matrix interfacial microstructure by CVI and PIP methods have been successful, resulting in the production of high strength and high fracture toughness SiC/SiC composites. Several joining processes using PIP, RS and mechanical fastener for composites are introduced. Dimensional stability under radiation damage has been studied by neutron and charged particle irradiation. The SiC/SiC composites prepared with Type-S SiC fiber with a stoichiometric composition did not exhibit mechanical property degradation. Based on the development of SiC composites, test module concepts to verify the advanced fluid systems including SiC/SiC/Be/He coolant blanket are presented. (orig.)