EQUILIBRIUM THERMODYNAMICS ANALYSES OF A COMPLEX THERMIT REACTION USED FOR CENTRIFUGAL-THERMIT PROCESS

The possible equilibrium products and their compositions of a complex thermite reaction which was used for centrifugal-thermit process have been performed by means of the free-energy minimization method. The effects of the composition of thermit, preheating temperature and inert addition on the equilibrium composition, the heat of reaction and the adiabatic temperature of the system were investigated. It shows that apart from Al₂O₃,Fe,Cr,Ni, in the equilibrium products exist TiC,Cr₇C₃,CrN,AlNi,AlNi₃,FeAl₂O₄,CaS and TiN. The intermetallics such as NiAl and Ni3Al in the equilibrium products increase with an increase in the aluminum content in the thermit. The CaO can act as desulphurizer. In addition, CaO decreases the adiabatic temperature of the system. The adiabatic temperature of the system increases with a rise in the preheating temperature.