Abstract
Laminated SiC whisker reinforced Al_2O_3 matrix ceramics with three and six layers were fabricated through hot-press method and their bending strengths and fracture toughness were evaluated by three-point bending tests, where Al_2O_3 layer was set to tension side and namely composite with higher V_fto compression side. The bending strengths of the materials with both three and six layers were lower than that of monolithic Al_2O_3. This result could be due to nucleation of crack around the interface between the Al_2O_3 layer and the neighboring composite layer. The fracture toughness in the three-layer materials was relatively higher than in the monolithic Al_2O_3 and in the six-layer materials. From the residual stress analysis considering the cooling process in the fabrication, compressive residual stress, which could restrict the crack growth, was confirmed near the crack tip only in the three-layer materials.
