Fabrication and Microstructure of BN Matrix Composites with Electrical Conductivity

摘要

BN ceramic is an advanced engineering ceramics with excellent thermal shock resistance, good workability and excellent dielectricity. TiB_2 ceramic has excellent electric conductivity, high melting points, and corrosion resistance to molten metal. Therefore, the composite consisting of BN and TiB_2 ceramics is expected to have a combination of above-mentioned properties, thereby can be used as self-heating crucible. In this paper, hot pressing technology was used to fabricate the high performance BN-TiB_2 composite materials. Microstructure and electric conducting mechanism were studied, and the relationship between the microstructure and physical property was discussed. The results show that the microstructure of composites has a great influence on the physical property of composites. The BN-TiB_2 composites with excellent mechanical strength and stable resistivity can be obtained by optimizing the processing parameter and controlling the microstructure of composites.