Effect of ZrO2 addition on vickers hardness of modified basalt glass-ceramics

Abstract

Improvement of mechanical properties of cordierite glass-ceramics using modified Egyptian basalt rocks by addition of different amounts of zirconia (ZrO2) was investigated. Crystallization behavior of modified basalt glass was studied by X-ray diffraction (XRD) and scanning electron microscope (SEM). The Vickers hardness of glass-ceramics containing different amounts of ZrO2 and formed at 1050°C for various heat-treatment time was compared. Toughness of the glass-ceramics increased with increasing the amount of transformable ZrO2, which process is probably caused by crack deflection due to the high stress field around transformed ZrO2.