Nucleation in a precursor glass for a Li2O-Al2O3-SiO2 glass ceramic Part 1. Nucleation kinetics

Abstract

The nucleation of the parent glass of a Li2O-Al2O3-SiO2 glass ceramic is determined. The two-step development method is applied utilizing a specially developed device which allows quantitative determination of nucleation rates despite of the strong tendency for nucleation. The influence of nucleation on the transmission of the glass ceramic is investigated to obtain criteria for optimal nucleation conditions for ceramization of the glass. Nucleation is markedly characterized by non-stationary behaviour. The existence of delay times which depend as well on development temperature as on thermal history of the glass is of great importance for the processing of the glass. The impact of nucleation kinetics on the production of the glass ceramic is explained by means of TTT diagrams.