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. 03, 2018
Filed:
May. 17, 2012
Koichi Sato, Tokyo, JP;
Masahiro Kubo, Tokyo, JP;
Masaaki Mizumura, Tokyo, JP;
Tohru Yoshida, Tokyo, JP;
Koichi Sato, Tokyo, JP;
Masahiro Kubo, Tokyo, JP;
Masaaki Mizumura, Tokyo, JP;
Tohru Yoshida, Tokyo, JP;
NIPPON STEEL & SUMITOMO METAL CORPORATION, Tokyo, JP;
Abstract
Provided is a plastic working method of steel including austenite, the method including: analyzing a strain ratio βx of an estimated breaking point which is specified during plastic deformation of the steel; heating a steel such that a local temperature Tis within a temperature range indicated by the following expression 1, when Trepresents a strain-induced-transformation-maximum-ductility-temperature in the unit of ° C. for the strain ratio βx, σLrepresents the standard deviation of a fitted curve of critical equivalent strain which depends on the strain ratio βx on a lower temperature side than T, σHrepresents the standard deviation of a fitted curve of critical equivalent strain which depends on the strain ratio βx on a higher temperature side than T, and Trepresents a local temperature in the unit of ° C. of the estimated breaking point; and plastically deforming the steel after heating:−2×σ+1.25×σ  (Expression 1).