Abstract: The relatively poor formability and spot weld fracture appearance of hot-rolled and heavy gauge cold-rolled low carbon steels (in which silicon is the primary deoxidant) have been attributed to manganese silicate stringer-type inclusions, generally found in this product. The addition of at least about 1/8 pound magnesium, per ton of steel cast, is shown to modify this deleterious inclusion morphology, with a resultant improvement in the ductility and weldability of such hot-rolled and the heavy gauge cold-rolled products.

Abstract: A method is disclosed for the deoxidation of open type steels, e.g. rimmed and capped steels, which are particularly useful in the production of sheet products with improved formability. The requisite amount of deoxidation in the ladle is achieved through the use of conventional deoxidizers, other than aluminum (preferably silicon carbide). Deoxidation in the mold is also achieved without the use of aluminum. Here, however, it is necessary that mold deoxidation be achieved through the use of magnesium, generally added in the form of a magnesium-nickel alloy.