Production method of low carbon aluminum killed steel

摘要

PROBLEM TO BE SOLVED: To suppress the deposition of AlN even in the continuous casting of low carbon aluminum-killed steel containing large amounts of Al.SOLUTION: In a continuous casting method of low carbon aluminum-killed steel, the low carbon aluminum-killed steel contains, by mass%, 0.01-0.20% C, 0.25-0.40% Mn, 0.03% or less Si, 0.005-0.030% P, 0.01-0.03% S, 0.063-0.12% Al, 0.0060% or less N, and the balance Fe with impurities. Ti is added to the low carbon aluminum-killed steel so as to satisfy equation: 0.010%Ti≤0.025% and the surface temperature of a cast piece at the upper part of a secondary cooling zone having a slab-solidified shell thickness of the cast piece of 10-30 mm equals to the deposition starting temperature of ALN or higher.EFFECT: The surface crack of the cast piece of the low carbon aluminum-killed steel due to the addition of the large amounts of Al can be prevented.SELECTED DRAWING: None