| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method for producing a high cleanliness steel having excellent fatigue service life by using an RH vacuum refining apparatus. SOLUTION: Decarburization-treatment is applied to molten iron by using a decarburization-refining furnace and the refined molten steel is tapped into a ladle and flux containing CaO and Al2O3, is added into the molten steel in the ladle and slag components are adjusted so that SiO2 content in the produced slag satisfies the range of 7-12 mass%. Thereafter, inert gas is blown into the molten steel in the ladle to stir the molten steel and successively, the vacuum refining is applied for >=30 min by using the RH vacuum refining apparatus.</p> |
