Nucleation and Crystallization of a Lithium Aluminosilicate Glass

An aluminosilicate glass of composition 61SiO 2 6Al 2 O 3 10MgO6ZnO·12Li 2 O·5TiO 2 (mol%) has been prepared by a melting process and investigated as far as crystallization is concerned. Glass‐ceramic is easily obtained because glass shows a high tendency to crystallize starting from 700°C. The crystalline phases evolve with temperature, showing the aluminosilicates to be the main phase up to 1050°C, followed by metasilicates and silicates, some of which have lower melting points. The titanates of Mg and Zn develop from the phase‐separated glass, soon after T g , and grow to form nucleation centers for the other crystalline phases. The evolution from phase‐separated glass to glass‐ceramic has been followed by many thermal, diffractometric, spectroscopic, and microscopic techniques.