Carbon-fiber-reinforced silicon carbide composites

The effects of AlN-Y2O3 on the fracture modes and mechanical properties of carbon-fiber reinforced carbide composites were investigated. The composites were fabricated by polymeric precursor pyrolysis-hot pressing. The bulk densities of the composites were measured by the Archimedes principle using deionized water as the immersion medium. The flexural and interlaminar shear strength was measured using three-point-bending test. For fracture toughness, single-edge-notched-beam test was applied. The fracture surfaces of the composites were observed by scanning electron microscopy, and the phases in the composites were identified by X-ray diffractometry with CuKα radiation and/or by energy-dispersive X-ray spectroscopy.