PROBLEM TO BE SOLVED: To provide a method for smelting molten steel, which can manufacture a BH steel sheet that causes a surface flaw at an extremely low rate, by controlling the quantity of solid solution Ti with high accuracy, while inhibiting the production of an alumina-based oxide as much as possible.;SOLUTION: In a process of smelting the molten steel by deoxidizing the molten steel through adding Ti to the molten steel which has been decarbonized into the carbon concentration of 0.01 mass% or less, adding Nb simultaneously when adding Ti or after having added Ti, subsequently further adding at least one element of Ce, La and Nd to the molten steel, and smelting the molten steel, the method for smelting molten steel for the bake-hardenable steel sheet includes: previously determining α which is defined by the expression of α=[sol. Ti]/[T. Ti], under a scheduled operation condition; adding Ti so that the concentration of [T. Ti] can be controlled to 0.9 times or more but 1.1 times or less of β which is defined by the expression of β=47.9×[N]/(14×α); and further adding Nb so that γ which is defined by the expression of γ=[C]-12×[Nb]/92.9 can be controlled to 0.0003 or more but less than 0.0025.;COPYRIGHT: (C)2009,JPO&INPIT
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