Microstructure and mechanical properties of yttria stabilized zirconia/silicon carbide nanocomposites

Fully stabilized 8YSZ/SiC nanocomposites were fabricated by hot-pressing technique, and the microstructure and mechanical properties were investigated. The fine SiC particulate inhibits densification and grain growth, this is due to the decreasing grain boundary diffusivity and mobility. Compared with the monolith, the composite system possesses narrow and homogeneous grain size distribution, and this tendency becomes more obvious with increasing SiC content. The fine and homogeneous microstructure improves the fracture strength; for instance, 5 and 20 vol% SiC nanocomposites showed 580 and 750 MPa of the strength, respectively. Fracture toughness was found to be improved due to the crack deflection at the crack tip.