Crystallization of leucite in potassium-alumino-silicate glasses

Abstract

Leucite crystals were successfully precipitated in a glass matrix which had the precise stoichiometric composition of leucite (KAISi(2)O(6)). Potassium silicate compound was first produced. Then, alumina was added to obtain the potassium aluminosilicate glass. Crystallization took place at 1550 degrees C for 24 h in air with a heating rate of 3 degrees C/min. The resultant material comprised a glass matrix where dense round polycrystalline clusters (200-300 mu m) of leucite were homogenously dispersed, seemingly acting as crack arresters. The leucite crystals (similar to 2-4 mu m thick and similar to 10 mu m long) were well-interlocked one to the other. The produced glass-ceramics exhibited good aesthetics with regards to their potential in dental applications.