Patent · US Expired

Process for producing high quality steel

US4675049A · kind A · utility

0Cited by
1References
17Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 4, 1986
Grant dateJun 23, 1987
Priority date
Expiry dateJun 4, 2006

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P10/20
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A process for producing high quality steel includes a first step of decarburizing the melt in a converter by top blowing with oxygen to a carbon content of less than 0.1% carbon. Next, carbon (comminuted coal) is delivered to the melt at a high velocity whereby the melt and slag will boil intensely with the carbon being delivered until the oxygen content of the melt is less than or equal to about 250-400 ppm oxygen and the carbon content is greater than or equal to about 0.04-0.07% carbon. In the third step, recarburization of the melt is effected in either the converter or a ladle whereupon a melt having as little oxygen as is reasonably possible; and a carbon content close to that desired is achieved. Finally, in a fourth step, the melt (which is now in a ladle) is treated with synthetic slag and with a material that is both deoxidizing and desulphurizing (i.e., metallic calcium) whereby a high quality steel is produced.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.