The toughening mechanism and mechanical properties of graphene-reinforced zirconia ceramics by microwave sintering

Abstract

The graphene/ZrO2 composites were fabricated by impregnating graphene dispersion into the ZrO2 ceramic matrix and sintered by microwave, and the microstructure and mechanical properties were investigated. The results showed that the graphene was well dispersed in the ceramic matrix and refined the grain size. The fracture toughness reached 8.62 MPa m1/2, confirmed by single-edge notched beam, which was 42% higher than that of the pure ZrO2. Also, the toughening mechanisms were investigated by micro-hardness testing and showed that a combination of crack deflection, micro-crack and crack bridging increased the fracture toughness.