Fabrication of SiC/SiC composites by means of in situ Crystallization of SiC Fibers

Abstract

A novel challenge, the in situ crystallization of Pre-SiC reinforced-fiber during the fabrication of SiC/SiC composites, has been made for cost effectiveness. Constituent parts of each fabricated material with various manufacturing conditions were assessed by microscopic observation. The depending issues of a prototype process were rather serious that the unwanted areas were conspicuously observed in several places, such as a residual oxide area, unsintered area, course matrix, porosity along the fiber-tows, and a huge scale of deformation on fiber-tows. Crystallization process of Pre-SiC fiber itself caused volume contraction about 24.5%, which result in formation of a gap between the fiber-tow and pyrolytic carbon (PyC) interface. The optimization has been successfully made for a new fabrication technique by controlling most of the known defects. As a result, defects are rarely observed in final product of composite material.