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:
Jul. 11, 1978
Filed:
Jul. 11, 1977
Katsuya Ikawa, Muroran, JP;
Yuichi Tanaka, Muroran, JP;
Riken Piston Ring Industrial Co. Ltd., Tokyo, JP;
Abstract
A ductile cast iron having a high tensile strength as well as a high elongation due to its matrix structure of finely mixed ferrite and pearlite grains obtained by the heat treatment. The material is pearlitic ductile cast iron and may be of ordinary ductile cast iron composition with the only exception that the manganese content being substantially less than 1%. A method of heat treatment for obtaining such a ductile cast iron, which is composed substantially of heating the material rapidly to form ferrite, austenite and graphite co-existing structure, and air cooling the same to change that structure into the above mentioned matrix structure.