Preparation of MgO-SiO2-Al2O3 composite particle by electrostatic adsorption method and its transformation to cordierite

Cordierite is an important member of aluminosilicate glass-ceramics family. This study reports on the feasible evolution of cordierite ceramics using composite particles prepared by electrostatic assembly method. SEM images proved the formation of SiO2-Al2O3-MgO composite particles. A mixture of SiO2, Al2O3, MgO raw ma-terials was also prepared by bead-milling method for comparison. The samples sintered at elevated temperatures were characterized by XRD, SEM, Raman spectroscopy and Raman mapping methods. Surface of silica particle in samples sintered at 1200 & DEG;C was covered by an amorphous magnesium silicate layer. Hexagonal cordierite formation started at about 1300 & DEG;C and transferred to orthorhombic phase when being heated at 1400 & DEG;C for 4 h. Characterization results proved that the uniform distribution of the raw material particles in the ESA method led to faster cordierite formation than in the BM method.