EFFECT OF MINERAL AND PHASE COMPOSITION OF STARTING MIXTURES ON SOLID-PHASE SYNTHESIS OF CORDIERITE

摘要

The paper examines the phase transformations and synthesis of cordierite under solid-phase sintering using different natural and synthetic minerals, including binary compounds (mullite, spinel, enstatite) formed in intermediate stages. It is established that the synthesis of cordierite takes two stages: formation of three thermodynamically stable binary oxide compounds such as magnesium–aluminum spinel, mullite, and enstatite and formation of cordierite from a multiphase mixture containing, besides binary compounds, free crystalline α-Al_2O_3 and SiO_2 oxides.