Investigating of sinterability and crystallization SiO2-CaO-MgO-Al2O3 glass- ceramic reinforced with ZrO2 nanoparticles

In this study, ZrO2 particle reinforced SiO2-CaO-MgO-Al2O3 glass-ceramic with amounts of 5, 10 and 20 wt% as reinforcement in presence CaF2 additive as sintering aid was investigated. The composites prepared by sinter- crystallization. The sinterability of samples was evaluated via relative density. The crystallin phases are characterized by X- Ray Diffraction. The samples examined by Scaning electron microscopy. The fracture toughness of composites was determined by the microindentation method. The reinforced glass ceramic with 10wt% ZrO2 was shown the higher fracture toughness than glass- ceramic. The residual stress amount due to volum expansion arien of Zirconia transformation caused to increase the fracture toughness.The addition 20 wt% ZrO2 rather than 10 wt% ZrO2 wasn,t created significant changes in fracture toughness because absence compelet sintering due to increasing viscosity.