Finite Element Analysis of Non-axisymmetric Stretch Flanging Process for Prediction of Location of Failure

Influence of Blank Holding Force on Stretch Flange Forming of Aluminum Alloy

“…The chemical composition of aluminum alloy 5052 sheet of 0.5 mm thickness is given in Table 1. For FE analysis a non-linear stress strain curve was considered as shown in fig.2 [7] .It was assumed that aluminum alloy sheet follows elastoplastic behavior with isotropic hardening rule. …”

“…The bolts were slightly tightened in such a way to prevent upward motion of the blank-holder and the workpiece. Experiments of stretch flanging process were performed on a hydraulic press equipped with a load cell of 2 KN [1,7]. A constant rate of displacement i.e.…”

“…The explicit finite element code ABAQUS /Explicit [7] is used to simulate the stretch flanging process in this study. Fig.4 indicates the FEM model of the stretch flanging process.…”

“…The material properties of the blank used in the simulation are as follows: ρ = 2680 kg/m 3 , E = 70.3 GPa, υ = 0.33. [7].Friction is modelled between the blank and the tool interfaces by using the Coulomb assumption in all cases as μ = 0.1 [7]. The damage initiation criteria (D) are defined as function of equivalent plastic strain for prediction of failure in flange.…”

“…Butcher et al [4] carried out finite element simulation of stretch flange forming of AA5182 of 1.6 mm using upper and lower bound damage based material models for prediction of formability and effect of void damage during forming operations. Simha et al [5] have utilized an extended stress based forming limit curve in order to predict necking in stretch flange forming of 1.6 mm thick AA 5754 and 1 mm thick AA 5182 aluminum alloy.Bhoyar et al [6] carried finite element analysis of superplastic forming process for front fender car panel ,which also an application of stretch flanging process, for prediction of formability of commercial AA 5182 sheets .Dewang et al [7] have predicted the location of edge crack occurred in stretch flange of AA 5052 in the stretch flange using finite element simulation. The objective of the present study is to investigate the influence of blank holding force on punch load variation and maximum load during stretch flange forming of 0.5 mm thick AA 5052 using finite element simulation.…”