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:
May. 05, 1981
Filed:
Aug. 23, 1979
Nobuo Ohashi, Funabashi, JP;
Yutaka Ono, Ichihara, JP;
Kiyohiko Nohara, Chiba, JP;
Junichi Shimomura, Chiba, JP;
Tetsuo Miyawaki, Chiba, JP;
Kawasaki Steel Corporation, Kobe, JP;
Nippon Kinzoku Co., Ltd., Tokyo, JP;
Abstract
Stainless steels for springs having a high strength and an excellent fatigue resistance are produced by heat treating austenitic stainless steels having such a composition that austenite stability index, Md.sub.30. is 0.degree. C. to +80.degree. C. at a final annealing temperature of 750.degree.-1,150.degree. C., subjecting the thus treated steels to a primary working at a temperature from Md.sub.30 to 500.degree. C. at a reduction rate of not less than 20% and then subjecting said steels to a secondary working at a temperature lower than Md.sub.30 at a reduction rate of not less than 30%.