Differential scanning calorimetry and thermodilatometry study of mechanically activated kaolin-CaCO₃ mixture with anorthite stoichiometry Available to Purchase

An influence of mechanical activation on the crystallization of high-temperature phases in kaolin-CaCO₃ mixture is investigated. Input raw materials are mixed according to the anorthite stoichiometry. Mechanical activation is performed using a planetary ball mill. Grinding program consists of seven different grinding periods varying from 5 min to 480 min. Samples are analyzed by differential scanning calorimetry (DSC) and thermodilatometry (TD) in the temperature interval from 780 °C to 1100 °C. Mechanical activation decreases the temperature of anorthite crystallization by ∼9 °C. Intermediate phase of gehlenite is fully suppressed by 240 min activation. The firing shrinkage at 1000 °C significantly increases from 2.9 % to 16.3 % due to mechanical activation. Activation for more than 240 min has no effect on further increase of firing shrinkage. Mechanical activation also decreases sintering temperature from 882 °C to 830 °C.