Variation analysis of auto-body aluminum alloy sheet metal assembly in self-pierce riveting

The forming limit curve (FLC) is used in sheet metal forming analysis to determine the critical strain or stress values at which the sheet metal is failing when it is under the plastic deformation process, e.g. deep drawing process. In this paper, the FLC of the AA6061-T6 aluminum alloy sheet is predicted by using a micro-mechanistic constitutive model. The proposed constitutive model is implemented via a vectorized user-defined material subroutine (VUMAT) and integrated with finite element code in ABAQUS/Explicit software. The mechanical behavior of AA6061-T6 sheet is determined by the tensile tests. The material parameters of damage model are identified based on semi-experience method. To archive the various strain states, the numerical simulation is conducted for the Nakajima test and then the inverse parabolic fit technique that based on ISO 124004-2:2008 standrad is used to extracted the limit strain values. The numerical results are compared with the those of MK, Hill and Swift analytical models.

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315 Two Stage Rolling Process Analyses of High Formability Aluminum Alloy Sheet Metal by Using Multi-scale Finite Element Method

The Proceedings of Conference of Kansai Branch ◽

10.1299/jsmekansai.2010.85._3-21_ ◽

2010 ◽

Vol 2010.85 (0) ◽

pp. _3-21_

Author(s):

Rong ZOU ◽

Tomiso OHATA ◽

Yasunori NAKAMURA ◽

Hiroyuki KURAMAE ◽

Hideo MORIMOTO ◽

...

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Aluminum Alloy ◽

Sheet Metal ◽

Rolling Process ◽

Alloy Sheet ◽

Aluminum Alloy Sheet ◽

Two Stage ◽

Multi Scale ◽

Element Method

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Springback Analysis of Aluminum Alloy Sheet Metals by Yoshida-Uemori Model

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.725.566 ◽

2016 ◽

Vol 725 ◽

pp. 566-571 ◽

Cited By ~ 1

Author(s):

Takeshi Uemori ◽

Kento Fujii ◽

Toshiya Nakata ◽

Shinobu Narita ◽

Naoya Tada ◽

...

Keyword(s):

Aluminum Alloy ◽

Sheet Metal ◽

Kinematic Hardening ◽

Yield Function ◽

Alloy Sheet ◽

Aluminum Alloy Sheet ◽

Sheet Metals ◽

Initial Anisotropy ◽

Hardening Rules ◽

Prediction Capability

During the last few decades, the enhancement of prediction capability of the sheet metal forming have been increasing dramatically. High accurate yield criteria and wokhardening model (especially, non-linear kinematic hardening model) have a great importance for the prediction of the final shapes of sheet metal. However, the predicted springback accuracy of aluminum alloy sheet metal is not still good due to their complicated plastic deformation behaviors.In the present research, the springback deformation of aluminum alloy sheet metals were investigated by finite element calculation with consideration of initial anisotropy and the Bauschinger effect. In order to examine the effect of the initial and deformation induced anisotropy on the springback deformation, several types of high accurate yield function and hardening rules are utilized in the present research. The calculated springback by Yoshida 6th yield function [1] and Yoshida-Uemori model [2] shows an excellent agreement with the corresponding experimental data, while the other models underestimate the springback.

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Springback Prediction of Aluminum Alloy Sheet under Changing Loading Paths with Consideration of the Influence of Kinematic Hardening and Ductile Damage

Metals ◽

10.3390/met8110950 ◽

2018 ◽

Vol 8 (11) ◽

pp. 950 ◽

Cited By ~ 2

Author(s):

Zhenming Yue ◽

Jiashuo Qi ◽

Xiaodi Zhao ◽

Houssem Badreddine ◽

Jun Gao ◽

...

Keyword(s):

Aluminum Alloy ◽

Sheet Metal ◽

Kinematic Hardening ◽

Material Model ◽

Alloy Sheet ◽

Ductile Damage ◽

Loading Path ◽

Aluminum Alloy Sheet ◽

Strain Paths ◽

Springback Prediction

Springback prediction of sheet metal forming is always an important issue in the industry, because it greatly affects the final shape of the product. The accuracy of simulation prediction depends on not only the forming condition but also the chosen material model, which determines the stress and strain redistributions in the formed parts. In this paper, a newly proposed elastoplastic constitutive model is used, in which the initial and induced anisotropies, combined nonlinear isotropic and kinematic hardenings, as well as isotropic ductile damage, are taken into account. The aluminum alloy sheet metal AA7055 was chosen as the studied material. In order to investigate springback under non-proportional strain paths, three-point bending tests were conducted with pre-strained specimens, and five different pre-straining states were considered. The comparisons between numerical and experimental results highlighted the hard effect of both kinematic hardening and ductile damage on the springback prediction, especially for a changed loading path case.

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