Title:
PRODUCTION OF CALCIUM-CONTAINING STEEL
Document Type and Number:
Japanese Patent JP3430642
Kind Code:
B2
Abstract:
PURPOSE: To manufacture a Ca-containing steel excellent in machinability by addition of Ca to a molten steel after the addition of specified amount of solid oxygen in the latter period of refining of the molten steel.
CONSTITUTION: At the time of manufacturing a free-cutting steel, a steel is melted and refined in an electric furnace, etc., and Pb is added as an element for improving machinability. In the latter period of refining, a raw material containing oxygen as a solid state, such as NiO and Fe2O3, is added at the rate of 10 to 80kg oxygen per 1ton molten steel to increase [O] concentration in the molten steel and then Ca is added. Ca is made into CaO and then CaO-Al2O3-SiO2 compound is produced in the molten steel to transform 100% of added Ca into anorthite or gehlenite. Thus, machinability of the steel products made of this molten steel is improved.
Inventors:
Toshiyuki Kawamura
Application Number:
JP15269394A
Publication Date:
July 28, 2003
Filing Date:
June 09, 1994
Export Citation:
Assignee:
Daido Steel Co., Ltd.
International Classes:
C21C7/00; (IPC1-7): C21C7/00
Domestic Patent References:
| JP4280911A | ||||
| JP494612A | ||||
| JP504452B1 | ||||
| JP4621818B1 | ||||
| JP438340B1 |
Attorney, Agent or Firm:
Kazuo Yoshida
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