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:
Jun. 20, 1978
Filed:
Jun. 04, 1975
Applicant:
Inventors:
Katsuya Ikawa, Muroran, JA;
Yuichi Tanaka, Muroran, JA;
Assignee:
Riken Piston Ring Industrial Co. Ltd., Nishishinbashi, JA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C21D / ;
U.S. Cl.
CPC ...
148138 ; 148 35 ; 148139 ;
Abstract
A spheroidal graphite cast iron containing some carbide stabilizing elements to have the maximum strain rate sensitivity factor of more than 0.3 and having very refined grain matrix structure, so that having an improved toughness at room temperature and having a matrix which is composed of fine austenite and fine ferrite grains and superplastic properties at the temperature between the eutectoid transformation temperature range and 50.degree. C higher than that temperature range; and the method of heat treatment to obtain the said spheroidal graphite cast iron.