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. 06, 1988
Filed:
Feb. 06, 1987
Atsushi Itami, Kimitsu, JP;
Kazuo Koyama, Kimitsu, JP;
Hiroshi Katoh, Kimitsu, JP;
Nobuhiko Matsuzu, Kimitsu, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
An r value of a hot-rolled steel sheet is enhanced by: a specific composition consisting of not more than 0.015 wt % of C, from 1.0 to 2.5 wt % of Mn, from 0.005 to 0.10 wt % of Al, from 0.01 to 0.06 wt % of Nb, from 0.01 to 0.1 wt % of Ti; and, controlled rolling, characterized by in the rough rolling, imparting, in a temperature range of from 980.degree. to 1100.degree. C., a heavy reduction of not less than 20% per pass to the steel sheet; completing a finishing rolling at from Ar.sub.3 to 930.degree. C. and maintaining a total reduction at a temperature of not more than Ar.sub.3 +150.degree. C. to not less than 90%; and, coiling at a temperature of from 600.degree. to 800.degree. C.