Study of local silica sand deposits for producing leucite glass-ceramics for dental applications

Abstract

The objective of this research work was to examine the potential of using local silica sand from Terengganu, as a raw material in producing leucite glass-ceramics for dental applications.  The characterization of the silica sand was carried out using chemical analysis and X-ray fluorescence (XRF) analysis. The study also focused on the effect of temperature and soaking time of sintering on the formation and properties of leucite glass-ceramics for dental applications.  A starting glass composition of weight %; 64.2% SiO₂, 16.1% Al₂O₃, 13.6% K₂O, 5.10% Na₂O, 0.5% TiO₂ and 0.5% LiO₂ was melted in an electric furnace, and then quenched in cool water to produce glass frit. The glass powders were ball milled and compressed to form 13mm diameter discs.  The discs were sintered at 700°C,750^°C, 800^°C and 850^°C for 1.0, 3.0, 6.0, 9.0 and 12.0 hours. The XRD analysis results show that the glass powders produced leucite phase as the major phase at certain temperature and soaking time of sintering.   The sanidine (KAlSi₃O₈) phase was also formed as the minor phase.  The properties of sintered discs were studied using field emission scanning electron microscopy (FESEM), Vickers micro hardness and universal testing machine (UTM).  Based on the microhardness and three point bending test results,  the strength of the samples increased as the soaking time of sintering increased.

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GRAPHICAL ABSTRACT