| 摘要 |
<p>PURPOSE:To provide a producing method of stainless steel having ultrahigh cleanliness by softening and reducing mom-metallic inclusions in the stainless steel. CONSTITUTION:In refining of the molten stainless steel, the molten steel is refined to <=30ppm aluminum and 60-120ppm oxygen and tapped into a ladle, and by injecting a flux containing <=0.3% calcium oxide and calcium fluoride based on the wt. of molten steel, as the main components into the molten steel in this ladle together with an inert gas, the secondary refining is executed. Desirably, after the above treatments, by making pure calcium content of calcium alloy in either or both of the ladle and a tundish >=0.01% based on the weight of the molten steel, the non-metallic inclusion is softened and reduced and the stainless steel having ultrahigh cleanliness can be produced. In the production of an extremely fine wire, foil, etc., required inclusion cleanliness, drawability, fatigue strength and surface quality are drastically improved.</p> |
