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:
Apr. 09, 2002
Filed:
Mar. 30, 2000
Yoshiyuki Ueshima, Tokai, JP;
Kohsaku Ushioda, Kimitsu, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
An iron scrap having a composition comprising iron and iron-soluble elements in the sum of 100 mass %, and containing Cu, elements of the Groups IIIa, VIII, Ib, IIb, IIIb, IVb and Vb having affinity with Cu, and unavoidable impurities, is melted in an oxygen-containing atmosphere. A predetermined amount of C, and whenever necessary, a predetermined amount of at least one of Cr and Mo and/or a predetermined amount of at least one of Mn, V and Ti, are added to the molten steel. The molten iron is then separated into an Fe-enriched layer and a Cu-enriched layer under the molten state. Cu and the above elements having affinity with Cu are separated and precipitated into the Cu-enriched layer by utilizing the difference of the specific gravity between the layers. According to this method, impurity elements detrimental to the stable production of a steel material having a homogeneous property, such as Cu, Sn, etc., can be removed economically and efficiently when the iron scrap is recycled.