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:
Nov. 05, 1991
Filed:
May. 15, 1990
Hiroki Tanaka, Nagoya, JP;
Shin Tsuchida, Nagoya, JP;
Sumitomo Light Metal Industries, Ltd., Tokyo, JP;
Abstract
The present invention provides a method of producing a hardened aluminum alloy sheet comprising the steps of casting an aluminum alloy containing 4.0 to 6.0% Mg in a conventional including, homogenizing, hot rolling, cold rolling, intermediate annealing and stabilizing treatment, the improvement which comprises: the aluminum alloy is provided as an Al-Mg-Cu alloy containing, in addition to Mg, 0.05 to 0.50% Cu; and the Al-Mg-Cu alloy is subjected to a final intermediate annealing treatment comprising a heating to temperatures of 350.degree. to 500.degree. C. and rapid cooling to temperatures of 70.degree. C. or less at a cooling rate of 1.degree. C./sec or more and a finishing cold rolling with a reduction of at least 50%, followed by the stabilizing treatment, thereby providing a hardened aluminum alloy sheet having a superior corrosion resistance together with high levels of strength and formability. In the above production method, the finishing cold rolling with a reduction of at least 50% may be followed by coating and baking operations carried out under application of tension to the alloy.