Study on Synthesis Mechanism of Magnesium Ferrite by Non Isothermal Kinetics

摘要

Magnesium ferrite is a kind of main bonding phase in magnesia refractory materials. The synthesis process of magnesium ferrite was studied by thermal analysis method in the paper. The DSC experiment of the synthesis reaction of magnesium ferrite was made with active magnesia and chemical reagent Fe_2O_3 in static air atmosphere at different temperature and as a scanning rate as 10, 15 and 20 K/min. The kinetics parameters, the mechanism function and the activation energy of the synthesis reaction of magnesium ferrite were calculated by Kissinger equation, Ozawa equation and Achar-Brindley-Sharp-Wendworth equation. The DSC curves of the mixture of active magnesia and chemical reagent Fe_2O_3 show that the formation of magnesium ferrite is evident from 1500 K to 1650 K, the activation energy of the reaction is around 626.832 to 652.60 kJ/mol, and the function of the reaction mechanism of magnesium ferrite is fit for the model of nucleation forming and growing at random.