Effect of the Composition of Raw Materials and Nucleating Agents. Crystallization behavior of nepheline-pyroxenic glass

Different combination of raw materials and nucleating agents were incorporated in the batch of nepheline-pyroxene glass to demonstrate their effect on the crystallization process. The effect of TiO2, Cr2O3 and LiF with respect to crystallization of base glass was studied by differential thermal analysis (DTA).These materials improved the crystallization of glass between 50 to 150°C of heat treatment. When LiF+TiO2 and TiO2+Cr2O3 were put together in the glass batches, the rate of crystallization of glass was increased in the same manner. The presence of TiO2+LiF+Cr2O3 improved the crystallization of the glass by decreasing the heat temperature by about 60°C. CaO/MgO and CaO/Na2O ratios played an important role in the rate of crystal growth. The increase in the CaO/MgO ratio lowers the crystallization temperature by values ranging between 37 and 46°C.