Pressureless sintering and mechanical properties of mica glass–ceramic/Y-PSZ composite

Mica glass–ceramic composites toughened by 5, 10 and 15 wt.% partially stabilized zirconia (Y-PSZ) were prepared via pressureless sintering. Sinterability of composites was investigated in the temperature range of 1060–1170 °C using soaking time of 240 min. The sintered specimens were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) methods. The results revealed that during sintering, the dissolution of Y-PSZ occurred in the residual glass which caused the formation of zircon and transformation of tetragonal to monoclinic zirconia. Mechanical properties of the sintered samples such as bending strength, Vickers micro-hardness and fracture toughness were also investigated. Measurements showed that addition of 15 wt.% ZrO2 to the mica glass–ceramic matrix increased the bending strength from 50.91 ± 10.50 to 132.47 ± 13.80 MPa. Fracture toughness was also improved up to 1.37 ± 0.14 MPa m1/2.