The influence of titanium as a desferoidizing element on the stability of production of magnesium cast irons with compacted graphite

Abstract

The thermodynamic calculations and the obtained dependence of the Gibbs energy of the reactions of formation of titanium oxide, titanium sulfide, titanium nitride and titanium carbide in the melt of magnesium cast iron on their concentrations and melt temperature have been presented in the article. It has been shown that titanium, regardless of the concentration in melt, will primarily perform a deoxidizing effect, interacting with the oxygen. The lower negative values of the Gibbs energies are characterized by the reactions of the interaction of titanium with sulfur, at a concentration of the latter 0.01%, which indicates a decrease in the probability of such reaction occurrence. From a thermodynamic point of view, the reactions of titanium nitride and carbide formation are less probable. The values of the Gibbs energy of the interaction reaction of titanium depend to a large extent on the melt temperature. It has been found that for a more complete realization of the desulfurizing properties of titanium, it is advisable to enter the composition of cast iron during melting and overheating, when the melt temperature reaches maximum values. The optimal conditions for obtaining magnesium cast irons with compacted graphite has been determined. It has been found that the addition of titanium to magnesium cast iron, as a desferoidizing element containing 0.035% S, has a positive effect on stabilizing the formation of compacted graphite.