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:
Jul. 31, 1984
Filed:
Mar. 05, 1982
Yoshio Baba, Nagoya, JP;
Teruo Uno, Nagoya, JP;
Sumitomo Light Metal Industries, Ltd., Tokyo, JP;
Abstract
An aluminum alloy material having a high strength, small grain size, good resistance to stress corrosion cracking and very high degree of workability is produced from an aluminum base alloy consisting essentially of 5.1 to 8.1 wt. % Zn, 1.8 to 3.4 wt. % Mg, 1.2 to 2.6 wt. % Cu, up to 0.2 wt. % Ti and at least one of 0.18 to 0.35 wt. % Cr and 0.05 to 0.25 wt. % Zr, the balance being aluminum and impurities by an improved production method described in detail in the disclosure. The improved method is particularly characterized by a special annealing step in a continuous annealing furnace under the application of a tension not exceeding 2 kg/mm.sup.2 to a coiled alloy sheet to be annealed, the annealing including rapid heating of the coiled alloy sheet to a temperature of 400.degree. to 500.degree. C. at a heating rate exceeding 50.degree. C./min.