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:
Jan. 06, 1987
Filed:
Oct. 19, 1984
Applicant:
Inventors:
Toshio Yanagiya, Aichi, JP;
Kenji Isokawa, Aichi, JP;
Hisashi Ohta, Aichi, JP;
Hideaki Inaba, Aichi, JP;
Assignee:
Daido Tokushuko Kabushiki Kaisha, Nagoya, JP;
Primary Examiner:
Int. Cl.
CPC ...
C21D / ;
U.S. Cl.
CPC ...
420127 ; 148 121 ; 148319 ;
Abstract
An improved steel for cold forging for machine structural use, particularly, case hardening steel, contents of Al, N and Nb are selected to satisfy a specific corelation therebetween, and the amounts of O and S are controlled. The steel is resistant to cracking at the cold forging, and growth of austenite crystals to coarse grains during carburizing or carbonitriding is prevented. Disclosed are preferable structure of the steel and rolling conditions to obtain the structure, and conditions for continuous casting of the steel.