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. 28, 2015
Filed:
Aug. 24, 2010
Katsuhiro Sasai, Futtsu, JP;
Wataru Ohashi, Futtsu, JP;
Katsuhiro Sasai, Futtsu, JP;
Wataru Ohashi, Futtsu, JP;
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
Abstract
The present invention provides ultralow carbon thin gauge steel sheet and a method for producing the same where coalescence and growth of inclusions in the molten steel are prevented and the inclusions are finely dispersed in the steel sheet, whereby surface defects and cracks at the time of press forming are prevented, growth of recrystallized grains at the time of continuous annealing is promoted, and a high r value (r value≧2.0) and elongation (total elongation≧50%) are exhibited, that is, ultralow carbon thin gauge steel sheet excellent in surface conditions, formability, and workability comprised of, by mass %, 0.00030.003%≦C≦0.003%, Si≦0.01%, Mn≦0.1%, P≦0.02%, S≦0.01%, 0.0005%≦N≦0.0025%, 0.01%≦acid soluble Ti≦0.07%, acid soluble Al≦0.003%, and 0.002%≦La+Ce+Nd≦0.02% and a balance of iron and unavoidable impurities, said steel sheet characterized by containing at least cerium oxysulfite, lanthanum oxysulfite, and neodymium oxysulfite.