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:
Sep. 03, 2013
Filed:
May. 12, 2011
Dhiren Panda, Blytheville, AR (US);
Neal Ross, Armorel, AR (US);
Gary Mcquillis, Blytheville, AR (US);
Jerome Jenkins, Blytheville, AR (US);
Dhiren Panda, Blytheville, AR (US);
Neal Ross, Armorel, AR (US);
Gary McQuillis, Blytheville, AR (US);
Jerome Jenkins, Blytheville, AR (US);
Nucor Corporation, Charlotte, NC (US);
Abstract
A method of desulfurizing steel including steps of forming a slag over a molten metal, drawing a vacuum to less than 5 torr over the slag and molten metal, stirring the molten metal and slag, and deoxidizing and desulfurizing the molten metal and slag to degas the steel reducing at least sulfur, nitrogen, oxygen, and hydrogen contents, and reducing activity of oxygen in the molten metal to less than 30 ppm. The method includes forming a slag composition after degassing the steel comprising CaO between about 50 and 70% by weight, SiObetween about 20 and 28% by weight, CaFbetween about 5 and 15% by weight, MgO not more than 8% by weight, AlOnot more than 1% by weight, and a combination of FeO+MnO not more than 2% by weight, where the sum of CaO+CaF+SiO+MgO is at least 85% by weight.