Abstract
Ti-stabilized extra-low carbon steel sheet has excellent deep drawability.
A series of investigations on vacuum decarburization, deoxidation and Ti addition has been carried out. The followings have been found through these trials, and Ti-stabilized steel (≤0.006%C) has been successfully manufactured.
(1) In order to obtain extra-low carbon content, it is necessary that the DH vessel bottom should have a large area and a shallow steel bath.
(2) To obtain suitable Ti content, complete Al deoxidation is necessary before Ti addition.
(3) Too long DH treatment after alloy additions is ineffective to eliminate oxide inclusion.
(4) Much amount of oxide inclusion is located near the skin of an ingot, and can be cut off by hot scarfing after slabbing.
(5) Petrolic mold coating material or a cast iron stool causes an increase in carbon content of ingots.
