Preparation and Characterization of β-Spodumene and β-Eucryptite using Sol-Gel Methods

Two important phases, β-Spodumene and β-Eucryptite, from Lithia-Alumina-Silica ternary system were prepared by sol-gel methods using tetraethylorthosilicate, aluminum nitrate, and lithium chloride as starting materials. XRD, TGA, DTA, and dilatometer tests were used to distinguish the phase purity, crystallization, and the thermal expansion of the phases. The results showed that only pure β-Spodumene or β-eucryptite was formed depending on the stoichiometric ratio of the starting materials. The crystallization of β-eucryptite was started at 700˚C, while β-Spodumene was crystallized above 1000˚C. The highest thermal expansion coefficients of β-Spodumene and β-eucryptite, measured between room temperature and 800°C, were (-0.5×10-6/˚C) and (-4.2×10-6/˚C) respectively

کلیدواژه ها:

β-Spodumene ، β-Eucryptite ، low thermal expansion