Effects of carbon black content on the microstructure and properties of carbon/ceramic conductive composites

Carbon/ceramic conductive composites have been widely used in many fields such as aerospace, industrial heating and health care due to the excellent characteristics of the ceramic matrix and carbon-based conductive fillers.In this paper, carbon/ceramic conductive composites were prepared with a ceramic matrix (albite, diopside and quartz) and carbon-black (CB) conductive filler, and the effects of the CB content on the phase composition, microstructure, sintering performance, mechanical and electrical properties of the composites were studied.The results showed that CB particles entered the pores among the ceramics particles when the CB content increased from 0 w/% to 5 w/%, accompanied with a degradation of the porosity, water absorption, sintering performance and electrical conductivity but an enhancement of the mechanical properties.With a further increase in the CB content, the number of the CB particles on the surfaces of the ceramic particles was increased and the porosity began to increase while the mechanical properties were degraded.During the increase in the CB content, there was little variation in the sintering properties but the electronic conductivity decreased a lot.