The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 20, 1981
Filed:
Oct. 16, 1979
Applicant:
Inventors:
Assignee:
Nippon Steel Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C21C / ;
U.S. Cl.
CPC ...
75 52 ; 75 58 ; 75 60 ; 75257 ;
Abstract
Molten steel in desiliconized, dephosphorized and decarburized in a three-step sequence. In the first-two steps the melt is agitated. In the first step the temperature is also maintained at between 1480.degree.-1380.degree. C. while oxygen is introduced until the silicon content is reduced to 0.20%. In the second step a flux consisting essentially of CaO and 0.2-0.5 parts by weight of CaCl.sub.2 and/or KCl is introduced while maintaining the basicity of the slag at between 3.5-8.0 and the T.Fe value at between 3-10%. The third step involves blowing oxygen onto this melt without using a refining flux.