Microstructure and properties of SiC-reinforced Si3N4 ceramic

Silicon nitride ceramic was reinforced with SiC whiskers. The microstructure developed was characterized using electron microscope. The four-point bend strength of the resultant composite was measured both at room and at elevated temperatures up to 900 degrees C. The comparison of strength values for the resultant composite with that of the unreinforced Si3N4 ceramic showed a noticeable increase both at room and high temperature. The parameters controlling mechanical properties of the composite and its correlation to the microstructure developed during processing are discussed.