A different approach for considering the effect of non-proportional loading path on the forming limit diagram of AA5083

Material parameter identification within an integrated methodology considering anisotropy, hardening and rupture

“…For this purpose, tensile tests up to rupture and numerical simulations were used by the authors in order to calibrate the fracture criteria parameters. Zhalehfar et al (2013) predicted the effect of strain path change on the forming limit diagram (FLD) at rupture by using a numerical approach and the uncoupled Cockroft-Latham (CL) fracture criterion. Björklund et al (2013) also adopted the uncoupled CL fracture criterion and performed a comparison between experimental results coming from simple mechanical tests and FE simulations, to calibrate the criterion.…”

Path independent limiting criteria in sheet metal forming

“…The major limitation of the FLD is shown in Fig. 1 which is illustrated by Graf and Hosford [4] and Zhalehfar et al [7] experimentally. The experimental results reveal that the FLD for bi-linear strain path is not static, rather it is an inherently dynamic limit for sheet metal forming.…”

“…The sheet metal forming is different S.K. Paul / Journal of Manufacturing Processes xxx (2015) xxx-xxx [4] (b) uniaxial and plane strain pre-strain paths; pre-strain given in parallel to rolling direction (RD) of Al alloy A1611T4 [4] (c) uniaxial and plane strain pre-strain paths; pre-strain given in parallel to transverse direction (TD) of Al alloy A1611T4 [4] (d) uniaxial and biaxial pre-strain paths of Al alloy AA5083 [7]. from bulk forming.…”

“…The concept of the FLD has been extensively applied to predict formability to the sheet metal forming industry because of its simplicity, straightforwardness and comfort of use. The FLC is dynamic in nature, whose shape and position significantly alter with strain paths [3][4][5][6][7][8][9]. Therefore, the use of conventional FLD might be restrictive because the sheet metals experience nonlinear strain paths during the real industrial forming operations.…”

An extended Modified Maximum Force Criterion for the prediction of localized necking under non-proportional loading

“…A failure surface in function of the loading mode and prestrain level has been proposed by Werber et al (2013), who conducted nonlinear straining experiments in order to identify the surface parameters. Ductile fracture criteria have been used for the prediction of forming limits under non-proportional loading by Zhalehfar et al (2013).…”