Influence of ZnO and Heat Treatment Process on the Physical and Optical Properties of MgO-Al₂O₃-SiO₂Glass-Ceramics

Abstract

The influences of adding ZnO and the use of specific heat-treatment schedules on MgO-Al 2 O 3 -SiO 2 (MAS) glass-ceramic properties including crystallization, micromorphology, optical transmittance and Vickers-hardness were investigated. The XRD analysis proved that MgAl 2 O 4 and Al 2 ZnO 4 spinel are the major crystalline phases formed in the studied MgO-Al 2 O 3 -SiO 2 -ZnO (MASZ) glass ceramics. The addition of ZnO facilitated the crystallization of the MAS glass and resulted in a uniform and compact microstructure. The homogeneous distribution of microcrystals with average grain size less than 100 nm in the MASZ glass-ceramics contributed to the improvement of the corresponding transmittance in the visible range. In addition, the orthogonal heat-treatment experiment indicated that the crystallization time and nucleation time have a dominant effect on the microhardness of glass-ceramics, followed by decreasing effects of crystallization temperature and nucleation temperature.

Preparation and Properties of MgO-Al2O3-SiO2 Glass–Ceramics with Controllable Crystalline Phases

“…Hu et al discussed the influence of ZnO and heat treatments on the MAS glass-ceramics and found that the addition of ZnO could promote crystallisation and improve the microstructure. Further, the crystallisation and nucleation time affect the Vickers hardness of the glass-ceramics [27]. He et al investigated the influence of different nucleating agents (TiO 2 , ZrO 2 and TiO 2 + ZrO 2 ) on the crystallisation and properties of the MAS glass-ceramics.…”