In-situ Observations and Thermodynamics of the Chemical Reaction Between AIN Particles and Molten Slag

摘要

The present study further confirmed the formation of AlN in liquid high-Al TRIP steels during LMF processing and casting. The formed AlN inclusion particles will float out to the top slag where a reaction between AlN and reducible oxide in the slag will occur as confirmed by in-situ observation. Thermodynamic analysis showed that this reaction will generate Al_2O_3 and nitrogen gas into the slag. The potential of the slag to remove AlN from the steel/slag interface will depend on the amount of reducible oxides in the slag. It is believed that the kinetics of the AIN-slag reaction is fast and the gas volume generated from the reaction is significant, especially at low superheat. The released gas from this reaction may generate fine size bubbles in the mold slag and attention should be paid to the effect of these gas bubbles to casting performance.