Novel Method for Fabricating Carbon Nanofiber Toughened Silicon Carbide Composites

Carbon nanotube-reinforced ceramics are a promising class of materials that are plagued by extreme processing conditions which compromise the nanotubes, thereby inhibiting their ability to positively impact the ceramic composite. Applied Sciences, Inc. (ASI) proposes an innovative solution to this problem. Our process exploits the unique morphology of low-cost carbon nanofibers, upon which the ceramic matrix is built. This low-pressure process fully encapsulates the nanofiber - thereby protecting it from oxidation. This process also provides an intimate bond between the nanofiber and matrix that is of tailorable strength - thereby allowing optimization of the composite's fracture toughness. Ceramic nanocomposites made from this process are expected to engender a 25% improvement in fracture toughness over traditional fiber-reinforced ceramic matrix composites, and a 75% improvement in fracture toughness over monolithic silicon carbide. They will also exhibit oxidation resistance up to at least 1800 deg C. Our Phase I team, which includes 5 PhDs with a combined 100 years of relevant experience, will ensure the technical success of this effort and the broad dissemination of research results throughout the scientific community.