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:
Mar. 13, 1990
Filed:
Feb. 23, 1988
Susumu Sato, Chiba, JP;
Osamu Hashimoto, Chiba, JP;
Toshio Irie, Chiba, JP;
Nobuo Matsuno, Chiba, JP;
Kawasaki Steel Corporation, Kobe, JP;
Abstract
The present invention relates to the production of a cold rolled steel sheet having good ageing resistance and small anisotropy and adapted for deep drawing, which properties can satisfy concurrently the demands for the deep drawability and ageing resistance of the cold rolled steel sheet to be pressed and used for automotive exterior plate. The present invention has concurrently and satisfactorily solved the problems in the above described good ageing resistance and anisotropy, which problems had not hitherto been solved in the conventional method, by a method wherein a cold rolled steel sheet having such a limited composition that contains not more than 0.004% of C, 0.002-0.010% of a total amount of at least one element selected from Nb, Ti, V, Zr and W, and further occasionally contains not more than 0.0050% of B, is subjected to a continuous annealing at a temperature within the range of 700-950.degree. C. in the production of the cold rolled steel sheet according to the conventional method. The steel sheet obtained in the present invention can be advantageously used as a thin steel sheet adapted to be pressed, for example, into an automotive exterior plate.