Flanging is a commonly used sheet forming operation to increase the stiffness of a sheet panel and/or to create the mating surface for subsequent assemblies. This paper presents an energy approach to predict the onset of wrinkling during a shrink flanging operation. A curved sheet model is established to obtain the critical buckling stress in terms of stress state, geometry properties and material properties. The predictions of wave number agree well with the experimental results. The results indicate that the sensitivity of wave number on the plan view radius (PVR) increases as PVR decreases, and the wave number decreases with the increase of flange length. The critical flange length is significantly influenced by PVR, sheet thickness and material work-hardening, and is not sensitive to material strength and anisotropy.

Issue Section:
Technical Papers
Keywords:
forming processes, buckling, stress effects, manufacturing processes
Topics:
Buckling, Flanges, Stress, Waves, Geometry
1.
Wang
,
C. T.
,
Kinzel
,
G.
, and
Altan
,
T.
,
1994
, “
Wrinkling Criterion for an Anisotropic Shell with Compound Curvatures in Sheet Forming
,”
Int. J. Mech. Sci.
,
36
, pp.
945
–
960
.
2.
Hutchinson, J. W., and Neale, K. W., 1985, “Wrinkling of Curved Thin Sheet Metal,” Plastic Instability, Presses Ponts et Chausse´es, Paris, pp. 71–78.
3.
Neale
,
K. W.
, and
Tugˇcu
,
P.
,
1990
, “
A Numerical Analysis of Wrinkle Formation Tendencies in Sheet Metals
,”
Int. J. Numer. Methods Eng.
,
30
, pp.
1595
–
1608
.
4.
Chu, E. W., and Li, M., 1996, “The Onset and Growth of Elastic-Plastic Wrinkling of Aluminum Alloy Sheets,” NumiSheet’96, pp. 228–239.
5.
Tvergaard
,
V.
,
1999
, “
Studies of Elastic-Plastic Instabilities
,”
ASME J. Appl. Mech.
,
66
, No.
1
, pp.
3
–
9
.
6.
Zhang
,
L. C.
,
Yu
,
T. X.
, and
Wang
,
R.
,
1989
, “
Investigation of Sheet Metal Forming by Bending, Part II: Plastic Wrinkling of Circular Sheets Pressed by Cylindrical Punches
,”
Int. J. Mech. Sci.
,
31
, pp.
301
–
308
.
7.
Yu
,
T. X.
, and
Zhang
,
L. C.
,
1986
, “
The Elastic Wrinkling of an Annular Plate Under Uniform Tension on its Inner Edge
,”
Int. J. Mech. Sci.
,
28
, pp.
729
–
737
.
8.
Zhang
,
L. C.
, and
Yu
,
T. X.
,
1988
, “
The Plastic Wrinkling of an Annular Plate Under Uniform Tension on its Inner Edge
,”
Int. J. Solids Structure
,
24
, pp.
497
–
503
.
9.
Senior
,
B. W.
,
1956
, “
Flange Wrinkling in Deep-Drawing Operations
,”
J. Mech. Phys. Solids
,
4
, pp.
235
–
246
.
10.
Yu
,
T. X.
, and
Johnson
,
W.
,
1982
, “
The Buckling of Annular Plates in Relation to the Deep-Drawing Process
,”
Int. J. Mech. Sci.
,
24
, pp.
175
–
188
.
11.
Yossifon
,
S.
, and
Tirosh
,
J.
,
1984
, “
On Suppression of Plastic Buckling in Hydroforming Process
,”
Int. J. Mech. Sci.
,
26
, pp.
389
–
402
.
12.
Yossifon
,
S.
, and
Tirosh
,
J.
,
1984
, “
Buckling Prevention by Lateral Fluid Pressure in Deep-Drawing
,”
Int. J. Mech. Sci.
,
27
, pp.
177
–
185
.
13.
Cao
,
J.
, and
Boyce
,
M.
,
1997
, “
Wrinkle Behavior of Rectangular Plates Under Lateral Constraint
,”
Int. J. Solids Structure
,
34
(
2
), pp.
153
–
176
.
14.
Cao
,
J.
, and
Wang
,
X.
,
1999a
, “
An Analytical Model for Plate Wrinkling Under Tri-Axial Loading and Its Application
,”
Int. J. Mech. Sci.
,
42
, No.
3
, pp.
617
–
633
.
15.
Wang, X., and Cao, J., 1999b, “On the Onset of Wrinkling of Sheet with In-Plane Curvatures and Without Normal Constraint,” Transactions of North American Manufacturing Research Institution of SME, Vol. 27, pp. 55–60.
16.
Wang
,
X.
, and
Cao
,
J.
,
2000a
, “
On the Prediction of Side-Wall Wrinkling in Sheet Metal Forming Processes
,”
Int. J. Mech. Sci.
,
42
, No.
12
, pp.
2369
–
2394
.
17.
Wang, X., and Cao, J., 2001, “Wrinkling Limit in Tube Bending,” to appear ASME J. Eng. Materials and Technology, October.
18.
Yu, T. X., and Zhang, L. C., 1996, Plastic Bending: Theory and Applications, World Scientific.
19.
Li, M., Chandorkar, K. V., and Shah, K. N., 1996, “Experimental Study of Surface Distortion of Stretch and Shrink Flanging for Aluminum Autobody Alloys,” Alcoa Technical Center Report No. 96-481-018.
Copyright © 2001
 by ASME
You do not currently have access to this content.