Spark plasma sintering of ZrC–SiC ceramics with LiYO2 additive

Abstract Spark plasma sintering (SPS) of ZrC–SiC composite powders in the presence of LiYO 2 sintering additive was studied. The starting powders were obtained by a carbothermal reduction (CTR) of natural mineral zircon (ZrSiO 4 ), which provided an intimate mixing of in-situ created ZrC and SiC powders. This composite powder and LiYO 2 as additive were densified by spark plasma sintering. Microstructural features of the composite were investigated by XRD, SEM/EDS and AFM analysis. The sintered composite material possesses promising mechanical properties and excellent cavitation resistance which was observed with a cavitation erosion test. The values of Vickers microhardness and fracture toughness of the composite material are 20.7 GPa and 5.07 MPam 1/2 , respectively.