Compositional dependence of mechanical and wear properties of electroconductive ceramics

Some experimental works carried out at the Research Institute for Ceramics Technology (IRTEC) and National Physics Laboratory (NPL) on electroconductive ceramics are reviewed. The tests were mainly devoted to characterize mechanical and wear properties of electroconductive particulate composites based on silicon nitride and alumina matrices with reinforcement of nitrides, carbides, and borides. The focus of the study was to ascertain the influence of the sintering techniques and the amount and qualify of particle reinforcement on the mechanical and wear performances of the composites with respect to the matrix. The experimental results indicate that, besides the electroconductivity, some mechanical properties can be greatly enhanced by the introduction of a specific amount of intermetallic particles Unfortunately, the refractoriness of the starting matrix is at the same time reduced, making the composites more sensitive to the temperature effects.