The non-isothermal kinetics of cordierite formation in mechanically activated talc-kaolinite-alumina ceramics system

Abstract

The non-isothermal kinetics of cordierite formation from both non-activated and mechanically activated kaolinite + talc + alumina ceramic system was studied by differential thermal analysis (DTA). The mixture of kaolinite, talc and alumina was activated mechanically in a planetary mill, while amorphisation in the kaolinite, talc and alumina structure was studied by X-ray diffraction analysis. The activation energies depending on the conversion for cordierite formation were calculated from the DTA curves by using the non-isothermal method of Coats and Redfern at heating rates of 5, 10, 15 and 20 A degrees C min(-1). The mechanical activation of the kaolinite, talc and alumina mixture resulted in the decrease in activation energy values for cordierite formation.