Analysis of deep drawing process using FEA and FLD

Abstract

The forming limit diagram (FLD) of sheets is determined experimentally. The diagram is often called the Keeler-Goodwin diagram named for the engineers who defined it. There are several ways to determine the diagram, but the most commonly used method is the fixed-edge tensile method. FLD is defined in the coordinate system of the principal strains in the plane of the sheet. The problem of the limit deformability of sheets is presented in the papers [1] and [2]. In this paper, first a review of the experimental determination of the FLD will be given and then it will be integrated into a numerical simulation. The FLD of DC04 steel was determined and the case of deep drawing of a non-standard box section was analyzed using the Simufact.forming software. Two numerical experiments were performed, with two different lubrication conditions. Based on the results of the numerical simulation, it will be interpreted whether both cases satisfy, i.e. whether fracture occurs. The goal of the numerical experiment is to show how much using of FLD into the numerical simulation can improve the analysis of the sheet metal forming process.