Method for evaluating propriety of molding sheared edge

Abstract

The purpose of the present invention is to provide a technique for more precisely evaluating the propriety of forming a sheared material edge after preforming. Through a hole enlargement test on a metal plate after preforming, a strain gradient at a sheared edge is changed and a plurality of data of the deformation limit equivalent strain amount with respect to the strain gradient are calculated,and a relationship of a stretch flange deformation limit equivalent strain to the strain gradient is calculated from the plurality of data and the amount of pre-deformation equivalent strain. The propriety of forming a sheared edge for a metal plate subjected to pre-deformation by preforming is evaluated from a forming limit line L or formable region R of the sheared edge from the calculated relationship.

Description

Technical field [0001] The present invention relates to a technology for evaluating whether the edge of a material to be cut can be molded after one molding. For example, it relates to a technology that uses FEM (Finite Element Method, finite element method) simulation to evaluate whether or not the cut edges of stamped products for automobiles can be formed. Background technique [0002] As a method of evaluating whether or not moldability is possible at the shearing edge of a stamped product based on the deformation state near the shearing edge that has a large influence on the deformation limit, for example, there are judging methods described in Patent Documents 1 to 3. [0003] However, the above-mentioned methods for judging whether the cut edge of the stamped product can be formed are all evaluated on the edge of the material being cut without pre-deformation (one-shot molding), and for the material that is cut after pre-deformation. No consideration is given to the applica...

AI Technical Summary

Problems solved by technology

[0003] However, the above-mentioned methods for judging whether the sheared edge of the stamped product can be formed are all evaluated on the edge of the sheared material without pre-deformation (one-time forming). Applied in material edge without any consideration

[0004] Based on the above, there has been a problem with the accuracy of determining whether the sheared edge can be molded after one molding, and there is a problem that it is not clear whether it can be molded unless it is molded.

Images