1992 Volume 78 Issue 12 Pages 1794-1801
In order to improve or eliminate centerline segregation of continuously cast strand, various methods have been introduced but have to date produced satisfactory results. With a view to substantially solving the problem, the authors proposed a continuous forging technique based on a completely new solidification mechanism. In this method, the thickness of the strand is drastically reduced at the stage of final solidification by anvils so that the solute-enriched liquid in the mushy zone is discharged upstream and dendrite is crushed, and squeezed out into the liquid pool. The method was applied to No. 1 and No. 3 bloom casters at Mizushima Works to investigate the effect with various steel grades covering high carbon and low alloy steels. The segregation ratio of carbon C/C0 can be controlled to an aimed value between 0.61.0 by choosing an appropriate ratio of reduction to the unsolidified thickness. The qualities of final products such as wire and rod are remarkably improved. This paper presents the concept of this new technique, the effect of forging conditions on internal quality, and the results in final products.
