Investigation of Thermal Shock Behaviors for Machinable SiC/h-BN Ceramic Composites

The SiC/h-BN ceramic composites with different h-BN size were fabricated by Plasma Active Sintering (PAS) method. For the SiC/ nano-sized h-BN ceramic composites, when the h-BN content was increased, because the nano-sized h-BN crystals were homogeneously dispersed around the SiC grains of the matrix, the bending strength and fracture toughness of the composites decreased slowly, but the hardness decreased sharply, therefore the machinability and thermal shock resistance were improved noticeable.