Effects of Layer Thickness Ratio on Microstructure and Mechanical Properties of Al₂O₃-ZrB₂/Al₂O₃-TiCN Laminated Ceramics

Al₂O₃-ZrB₂/Al₂O₃-TiCN layered ceramics with different layer thickness ratios were prepared at 1650 ℃ by powder rotating layer method and vacuum hot pressing sintering technology with Al₂O₃ as the matrix phase of each layer, Y₂O₃ as the sintering aid of each layer, ZrB₂ and TiC_0.7N_0.3as the additive phases of AZ layer and AT layer, respectively. The effects of layer thickness ratio on the microstructure and mechanical properties were studied. The results show that with the increase of layer thickness ratio, the relative density, Vickers hardness and bending strength of laminated ceramics increase first and then decrease, while the fracture toughness increases gradually. When the layer thickness ratio is 4∶1, the relative density of the material is higher, the grains are relatively small and uniformly distributed, and good comprehensive mechanical properties are obtained, which are surface Vickers hardness of（19.28±0.25） GPa, bending strength of（637.68±20） MPa, surface fracture toughness of（7.81±0.35） MPa·m^1/2, respectively.