Title:
METHOD FOR REFINING ULTRALOW CARBON AND ULTRALOW SULFUR CHROMIUM-CONTAINING MOLTEN STEEL
Document Type and Number:
Japanese Patent JP3220233
Kind Code:
B2
Abstract:
PURPOSE: To easily obtain an ultralow carbon and ultralow sulfur chromium- containing molten steel without lowering the workability with a VOD by executing decarburization with SiO2-less slag in a refining using the VOD and using reducing and deoxidizing agent except Si under reduced pressure.
CONSTITUTION: [%C] is decarburized to 0.20-0.40% in a rough decarburizing furnace and Cr oxide produced in the carburization is reduced and recovered by using FeSi, and [%Si] in the molten steel is adjusted to ≤0.10wt.% and tapped into the VOD. In the VOD, the deoxidation is executed until the [%C] in the molten steel becomes the prescribed concn. (about ≤100ppm) by supplying oxygen and executing vacuum finish decarburization. Succesively, under the condition of holding the refining vessel at reduced pressure, the reducing and deoxidizing agent except FeSi, e.g. Al, etc., and desulfurizing flux are charged and stirred. By this method, without removing SiO2-rich slag after deoxidizing, and without lowering basicity of the slag, the ultralow carbon and ultralow sulfur chromium-containing molten steel can be produced.
Inventors:
Nishikori Regular
Hiroshi Nishikawa
Hiroshi Nishikawa
Application Number:
JP16965192A
Publication Date:
October 22, 2001
Filing Date:
June 26, 1992
Export Citation:
Assignee:
Kawasaki Steel Co., Ltd.
International Classes:
C21C7/00; C21C7/064; C21C7/076; C21C7/10; (IPC1-7): C21C7/00; C21C7/064; C21C7/076; C21C7/10
Domestic Patent References:
| JP3211214A |
Attorney, Agent or Firm:
Akihide Sugimura (5 outside)
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