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:
Sep. 28, 1993
Filed:
Sep. 18, 1992
Applicant:
Inventors:
Assignee:
Agency of Industrial Science and Technology, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C21D / ;
U.S. Cl.
CPC ...
148614 ; 148545 ; 148627 ; 148631 ; 148639 ;
Abstract
A unique method is proposed for the preparation of a body of an austempered ductile cast iron having a gradient of the mechanical property within the body by subjecting a body of a nodular graphite cast iron to an isothermal transformation treatment for austempering at a temperature in the range from 250.degree. to 450.degree. C. while the body has a temperature difference between two points or between two surfaces. The temperature difference can be produced by bringing the two points or two surfaces into contact with melts of a salt kept at different temperatures. A two-compartment salt-bath apparatus therefore is disclosed.