Controlling the electrical resistivity of porous silicon carbide ceramics and their applications: A review

Porous silicon carbide (SiC)-based ceramics are widely used in numerous applications of technical importance owing to their exceptional structural (e.g., excellent chemical, mechanical, and thermal stability) and functional (e.g., controlled electrical resistivity) properties. Porous SiC with controlled electrical resistivity is required for various advanced applications, for example, power electronic devices, semiconductor processing parts, fusion reactors, thermoelectric energy conversion, electromagnetic shielding, and environmental applications such as heatable filters. The electrical properties of sintered porous SiC are significantly affected by its chemical composition, processing conditions, and microstructure. This article reviews the influence of certain critical factors, such as the polytype, doping conditions, porosity (%), additive composition (oxide additives, element additives, metal nitride/carbide additives, etc.), and processing conditions on the electrical resistivity of porous SiC. Novel applications of porous SiC with controlled electrical resistivity are also discussed in this review.