Silicon Oxynitride Glasses and Glass-Ceramics Preparation and Properties

摘要

The purpose of this work was to study the change of physical properties of certain glasses and the corresponding glass-ceramics as a consequence of incorporation of nitrogen. Five series of glasses and their crystallized samples of Me-Si-Al-O-N (Me = Li, Ca, Mg, Ca+Mg, Mg+Li) system were prepared and studied. The criteria for selecting the composition within each system were: potential crystalline phases, castability of the melts below 1600 C, and in some cases, solubility of nitrogen in the melts. Melting of the glasses was performed in alumina or slip cast silica crucibles, in air and also in nitrogen, with acceptable results as far as their corrosion resistance was concerned. Nitrogen retention was of 61.7 - 74.2% for glasses melted in air (in covered crucibles) and 79.4 - 90.7% for those melted in nitrogen atmosphere. Glass transition and dilatometric softening temperature, thermal expansion coefficient and microhardness were measured. The crystallized samples were examined also by XRD and SEM.