Sintering, phase stability and room temperature mechanical properties of c-ZrO2 ceramics with TiO2 addition

An investigation has been carried out into the effect of TiO2 addition on the sintering, phase stability and room temperature mechanical properties of cubic zirconia (c-ZrO2). c-ZrO2 specimens containing TiO2 addition up to 10 wt% were produced by colloidal processing and pressureless sintering. The sintered density of the specimens decreased with increasing TiO2 content up to 1 wt% and further increase in TiO2 content led to a increase in the sintered density. XRD results showed that when the TiO2 amount was less than 5 wt%, the specimens were entirely single cubic phase; further addition of TiO2 (5 wt% or more) destabilized cubic zirconia phase and caused the formation of tetragonal phase. The amount of tetragonal phase increased with increasing TiO2 content in c-ZrO2 matrix. The room temperature mechanical properties of flexural strength and fracture toughness both increased with increasing TiO2 content.