Apr 04, 2012· D. Sichen, in Fundamentals of Metallurgy, 2005 9.5.1 Slag–metal mixing. In steelmaking, slag–metal mixing is a very common phenomenon and it occurs due to the shear at the slag–metal interface caused by excessive liquid steel flow. 37 This mixing leads to emulsification of steel in slag, which increases the total interfacial area and consequently the rate of slag–metal reactions.