Some aspects of behaviour of calcium in silicon killed steels

Abstract

Irregular flow can occur randomly in a casting sequence and mostly occurs in Si-Mn killed high C steels. Irregular flow increases reoxidation, mould level fluctuations and slag entrainment, all of which cause deterioration of the surface quality of the billets. The effect of calcium on irregular flow in billet casting of Si-Mn killed steels is discussed based on experience at two Corus steelplants, Scunthorpe and IJmuiden. Some theoretical aspects of calcium treatment are also discussed.