Effect of pressure loading cycle on spark plasma sintered ZrB2–SiC–Yb2O3 ceramics

Abstract: The influence of the pressure loading cycle on spark plasma sintered ZrB2–SiC–Yb2O3 ceramics was investigated. Spark plasma sintering consists of three stages, i.e., a heating-up, isothermal and cooling stage. Applying the load during isothermal stage allowed evaporation of volatile species. Applying the load during the heating-up and isothermal stages resulted in the entrapment of volatile species and the formation of nanometer-sized spherical SiO2 particles. The presence of SiO2 particles led to a large thermal residual stress, and improved fracture toughness in the ZrB2–SiC–Yb2O3 ceramics. [Copyright &y& Elsevier]