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:
Dec. 12, 1978
Filed:
Apr. 07, 1977
Moinuddin S Rashid, Rochester, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
The formability of high strength low alloy steel is improved while strength is substantially maintained or improved by first heating the steel to at least the lowermost eutectoid temperature of the steel to dissolve a substantial proportion of the carbides and nitrides (if nitrides are present) into the austenite and air cooling to substantially lower the yield strength and improve formability without significantly reducing tensile strength. The steel is then deformed to an amount equivalent to at least 2% strain on the tensile stress-strain diagram whereby the yield strength is substantially recovered. Preferably, the steel is then heat aged whereby the yield strength and tensile strength are each further raised.