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, 1998
Filed:
Sep. 29, 1995
Applicant:
Inventors:
Toyoaki Eguchi, Izumi-ku, JP;
Hiroshi Majima, Aoba-ku, JP;
Assignee:
Toa Steel Co., Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
C22C / ; C22C / ;
U.S. Cl.
CPC ...
148319 ; 420105 ; 420108 ; 420109 ;
Abstract
Steel for forming a gear by carburizing and quenching consisting essentially of: 0.1 to 0.35 wt. % C, 0.5 to 2.5 wt. % Si, 0.2 to 2.5 wt. % Mn, 0.01 to 2.5 wt. % Cr, 0.01 to 0.7 wt. % Mo, and the balance being Fe and inevitable impurities. The steel has an Ac.sub.3 point parameter (Ac.sub.3) and an ideal critical diameter (D.sub.I), the Ac.sub.3 point parameter being in a range of 850.degree. to 960 .degree. C., the ideal critical diameter (D.sub.I) being in a range of 30 to 250 mm, and the Ac.sub.3 point parameter (Ac.sub.3) and the ideal critical diameter (D.sub.I) being defined by the following equations.