Study on the formation of open-eye and slag entrainment in a gas stirred ladle

Laboratory experiments were carried out to study the phenomena related to open-eye formation in ladle treatment. Ga-In-Sn alloy with a melting temperature of 283 K was used to simulate the liquid steel, while MgCl2-Glycerol(87%) solution as well as HCl solution were used to simulate the ladle slag. No open-eye was formed at lower gas flow rates, but, occurred when gas flow reached a critical rate. This critical gas flow rate was found to depend significantly on the height of the top liquid. No noticeable amount of top liquid was observed in any of the samples taken from the metal bulk during gas stirring. To confirm this aspect, samples of slag-metal interface were taken around the open-eye in an industrial gas stirred steel ladle. No entrapped slag droplet was found in the solidified steel within the region between the interface and 2 cm from the interface. The accordance of the laboratory and industrial results suggests that the entrainment of slag into the steel bulk around the open-eye cannot be considered as the major contribution to inclusion formation.