Effect of Y3Al5O12 addition on the microstructural evaluation and mechanical properties of spark plasma sintered ZrB2-SiC composites

Abstract

In the present study, the addition of Y3Al5O12 (YAG) into the ZrB2-SiC composites was investigated. Composites were densified by spark plasma sintering (SPS) at 1850?C under a uniaxial pressure of 50 MPa for 20 min. Microstructural evaluation and mechanical properties were evaluated with a various content of YAG (1-5 wt%). Obtained results showed that sintering mechanism changed from solid state to liquid phase sintering with incorporation of YAG. The highest density (99.81 % RD) and fracture toughness (6.44 ? 0.23 MPa.m1/2) were obtained for the composite containing 5 wt% YAG after the SPS process. Although hardness and elastic modulus of samples were decreased with the increasing of YAG amount, measured values were comparable with the literature.