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:
Mar. 24, 2015
Filed:
Feb. 01, 2007
Shigeru Yonemura, Chiba, JP;
Akihiro Uenishi, Chiba, JP;
Shunji Hiwatashi, Chiba, JP;
Hiroshi Yoshida, Chiba, JP;
Tohru Yoshida, Chiba, JP;
Shigeru Yonemura, Chiba, JP;
Akihiro Uenishi, Chiba, JP;
Shunji Hiwatashi, Chiba, JP;
Hiroshi Yoshida, Chiba, JP;
Tohru Yoshida, Chiba, JP;
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
Abstract
According to exemplary embodiments of the present invention, using a fracture limit stress line obtained by converting a hole expansion ratio into a stress as a criterion for a fracture, the risk of fracture in a material can be evaluated quantitatively by comparing the relationship between data obtained from a numerical analysis using a finite element method and the fracture limit stress line. Thus, when determining a fracture limit in a stretch flange portion in a thin plate in a process including one or more deformation path variations, it is possible to obtain the fracture limit curve easily and efficiently and predict the fracture with high accuracy, and the risk of fracture upon press forming or crash can be evaluated.