| 摘要 |
<P>PROBLEM TO BE SOLVED: To accelerate decarburization reaction using oxygen contained in a manganese ore and recover manganese in the manganese ore into a molten steel with high yield, when smelting a manganese-containing low carbon steel by adding the manganese ore in decarburization refining under reduced pressure using a vacuum degassing facility. <P>SOLUTION: When smelting the manganese-containing low carbon steel by applying the decarburization refining under reduced pressure to the molten steel 3 in a vacuum chamber 5 of the vacuum degassing facility 1, the manganese ore is added in the vacuum chamber during the decarburization refining in accordance with the carbon concentration in the molten steel before adding the manganese ore in such a manner that the additive amount of the manganese ore is within the range satisfying formula (1): W<SB POS="POST">Mn</SB>=100×[%C]/(α×η<SB POS="POST">Mn</SB>) 0.0218≤α≤0.0436. In formula (1), W<SB POS="POST">Mn</SB>is the additive amount (kg/t) of the manganese ore, [%C] is the carbon concentration (mass%) in the molten steel before adding the manganese ore, η<SB POS="POST">Mn</SB>is a content (mass%) of the manganese in the manganese ore, and α is a constant. <P>COPYRIGHT: (C)2012,JPO&INPIT |
