Low fusion fluorophlogopite–leucite containing porcelain

Abstract Low fusion fluorophlogopite–leucite containing porcelain was prepared for use in dental restorations without metal substrates. Simultaneous crystallisation of fluorophlogopite and leucite phases with uniform evenly dispersed grains was achieved. Platy mica crystals and tetragonal leucite colonies crystallised in the porcelain to add strength through reinforcement of the glassy matrix. Further, chemical composition and the crystallisation process were regulated to avoid the formation of a parasitic forsterite phase. Crystallisation of fluorophlogopite begins at 620°C and of leucite at 750°C. Optimum crystallisation of the leucite–mica phase mixture in the porcelain was realised on heating between 850–930°C for 5–15 min.