The fabrication and mechanical properties of SiC/ZrB2 laminated ceramic composite prepared by spark plasma sintering

Laminated SiC/ZrB2 ceramic was fabricated by roll-compaction and spark plasma sintering at 1600 °C. A maximum fracture toughness of 12.3 ± 0.3 MPa m1/2 was measured for the sintered SiC/ZrB2 laminated ceramic. This significant improvement in fracture toughness can be attributed to the crack deflection along the interfacial layer and the presence of residual stresses in the sample. The effect of interlayer composition on the residual stresses was discussed in detail. It is observed that the residual thermal stress could be reduced by addition of ZrB2 particles to the SiC interlayer. The bending strength can be increased to 388 ± 44 MPa with the addition of 20 vol% ZrB2 to the SiC interlayer.