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:
Aug. 15, 1989
Filed:
Feb. 25, 1988
Kawasaki Steel Corporation, Kobe, JP;
Abstract
A method of manufacturing a cold-rolled steel sheet having a good deep drawability is disclosed, wherein a hot rolled steel sheet having a composition of C.ltoreq.0.0035%, Si.ltoreq.1.0%, Mn.ltoreq.1.0%, Al:0.005-0.10%, P.ltoreq.0.15%, N.ltoreq.0.0035%, S.ltoreq.0.015%, Ti: (48/14N(%)+48/32S(%)) or {4.times.(C(%)+N(%))}.about.(3.48/12C(%)+48/14N(%)+48/32S(%)) and Nb: (0.2.93/12C(%)).about.(93/12C(%))% is cooled within 2 seconds after the completion of finisher rolling and then at an average cooling rate of not less than 10.degree. C./sec until it arrives at a coiling step, and then the cooled steel sheet is coiled at a temperature of not more than 710.degree. C., subjected to a cold rolling at a reduction of not less than 50%, which was subjected to a continuous annealing in a heatcycle inclusive of heating from 400.degree. C. to 600.degree. C. at a heating rate of not less than 5.degree. C./sec and soaking at a temperature range of 700.degree. C.-Ac.sub.3 point for 1 second or more.