Study of forming limit diagram (FLD) prediction of anisotropic sheet metals using Gurson model in M-K method

This paper proposes an integrated hydraulic bulge and forming limit testing method and apparatus for sheet metals. By placing a PU (Polyurethane) plate between molds and uniformly applying hydraulic pressure to sheet metals, a biaxial stress-strain relationship and forming limit diagram (FLD) displaying both left and right sides were acquired using the same apparatus. An uniaxial tension test and traditional drawing test were conducted to compare the results obtained from the proposed hydraulic bulge and forming limit testing methods, respectively. A close correlation between the results of the stress-strain relationship and FLD in both comparisons verified the feasibility and capability of this integrated hydraulic testing method and apparatus for use with sheet metals.

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Experimental Determination of Anisotropic Properties and Evaluation of FLD for Sheet Metal Operations

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.106.39 ◽

2021 ◽

Vol 106 ◽

pp. 39-45

Author(s):

Araveeti C. Sekhara Reddy ◽

B. Sandeep ◽

J. Sandeep Kumar ◽

B. Sanjanna

Keyword(s):

Deep Drawing ◽

Grain Orientation ◽

Forming Limit Diagram ◽

Experimental Tests ◽

Rolling Process ◽

Forming Limit ◽

Drawing Process ◽

Sheet Metals ◽

Deformation Models

Most of the sheet metals in general exhibit high an-isotropic plasticity behavior due to the ordered grain orientation that occurred during the rolling process. This results in an uneven deformation yield property that tends to develop ears in case of deep-drawing operation. The deep drawing process is used for the production of cup-shaped articles having applications in automobiles, beverages, home appliances etc. It is essential to know the formability of sheet metals for minimisation of test runs and reducingthe defects. Forming Limit Diagram (FLD) is one of the methods for assessment of formability of sheetmetals. This paper describes various deformation models, yielding and an-isotropic properties and itsdetermination. Through experimental tests, FLD constructed for aluminium alloy AA6111 sheet metalhaving 0.9 mm thickness.

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Investigations on Influence of Geometric Parameters in Drawing of Perforated Sheet Metals

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.852.229 ◽

2016 ◽

Vol 852 ◽

pp. 229-235 ◽

Cited By ~ 1

Author(s):

G. Venkatachalam ◽

J. Nishanth ◽

M. Mukesh ◽

D.S. Pavan Kumar

Keyword(s):

Sheet Metal ◽

Software Package ◽

Parametric Analysis ◽

Forming Limit Diagram ◽

Simulation Software ◽

Geometric Parameters ◽

Forming Limit ◽

Sheet Metals ◽

Open Area ◽

Perforated Sheet

Forming Limit Diagram (FLD) is a resourceful tool to study the formability of sheet metals. Research on the formability of Perforated Sheet Metal is growing over the years as perforated sheet metal finds its applications in various fields. But finding FLD of perforated sheet metals is complex due to the presence of holes. Also, the hole size, shape and pattern, ligament ratio, thickness of the blank, percentage of open area influence the formability of a perforated sheet metal.In the present scenario, various simulation softwares have made the process of plotting FLD much easier, saving time and money. This paper is an attempt to predict the formability of mild steel perforated sheet metal through simulation software package LS Dyna. Also, Parametric analysis is performed to determine the influence of geometric parameters on the drawability of the perforated sheet metal.

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Measurement Methods for Forming Limit Diagram of Sheet Metals

Journal of the Japan Society for Technology of Plasticity ◽

10.9773/sosei.47.811 ◽

2006 ◽

Vol 47 (548) ◽

pp. 811-816

Author(s):

Yukihisa KURIYAMA

Keyword(s):

Forming Limit Diagram ◽

Measurement Methods ◽

Forming Limit ◽

Sheet Metals

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Prediction of Forming Limit Diagram Based on Damage Coupled Kinematic-Isotropic Hardening Model Under Nonproportional Loading

Journal of Engineering Materials and Technology ◽

10.1115/1.1431908 ◽

2002 ◽

Vol 124 (2) ◽

pp. 259-265 ◽

Cited By ~ 12

Author(s):

C. L. Chow ◽

X. J. Yang ◽

E. Chu

Keyword(s):

Damage Mechanics ◽

Kinematic Hardening ◽

Forming Limit Diagram ◽

Forming Limit ◽

Isotropic Hardening ◽

Strain History ◽

Sheet Metals ◽

Nonproportional Loading ◽

Localized Necking ◽

Theory Of Damage

Based on the theory of damage mechanics, an anisotropic damage coupled mixed isotropic-kinematic hardening plastic model for the prediction of forming limit diagram (FLD) is developed. The model includes the formulation of nonlinear anisotropic kinematic hardening. For the prediction of limit strains under nonproportional loading, a damage criterion for localized necking of sheet metals subjected to complex strain history is proposed. The model is employed to predict the FLDs of AL6111-T4 alloy. The predicted results agree well with those determined experimentally.

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