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:
Aug. 07, 2001
Filed:
Oct. 15, 1999
Other;
Abstract
Disclosed is a process for producing a shaft having improved strength without sacrificing machinability and cold workability. The process for producing a high strength shaft comprises the steps of: rolling or forging an alloy at a heating temperature of Ac,to 105° C. with a reduction in area of not less than 30%, the alloy comprising by weight carbon: 0.47 to 0.55%, silicon: 0.03 to 0.15%, manganese: 0.20 to 0.50%, molybdenum: 0.08 to 0.30%, sulfur: 0.005 to 0.035%, boron: 0.0005 to 0.005%, titanium: 0.05 to 0.20%, nitrogen: not more than 0.01%, aluminum: 0.005 to 0.05%, and manganese+molybdenum: 0.45 to 0.70% with the balance consisting of iron and unavoidable impurities, thereby producing a steel product having a hardness after rolling or forging of 85 to 97 HRB; and induction hardening the steel product to obtain a shaft, as shown in FIG.,, having a hardening depth ratio (distance from the surface to a position of 500 HV/radius of component) of not less than 0.25 and an austenitic grain size number as specified in JIS G 0551 of not less than 7.