Single point incremental forming (SPIF) is plagued by an unavoidable and unintended bending in the region of the sheet between the current tool position and the fixture. The effect is a deformation of the region of the sheet in between the formed area and the fixture as well as deformation of the already formed portion of the wall, leading to significant geometric inaccuracy in SPIF. Double sided incremental forming (DSIF) uses two tools, one on each side of the sheet to form the sheet into the desired shape. This work explores the capabilities of DSIF in terms of improving the geometric accuracy as compared to SPIF by using a novel toolpath strategy in which the sheet is locally squeezed between the two tools. Experiments and simulations are performed to show that this strategy can improve the geometric accuracy of the component significantly by causing the deformation to be stabilized into a local region around the contact point of the forming tool. At the same time an examination of the forming forces indicates that after a certain amount of deformation by using this strategy a loss of contact occurs between the bottom tool and the sheet. The effects of this loss of contact of the bottom tool on the geometric accuracy and potential strategies, in order to avoid this loss of contact, are also discussed.

References

References
1.
Huang
,
Y.
,
Wang
,
Y. J.
,
Cao
,
J.
, and
Li
,
M.
, 2007, “
Prediction of Forming Limit in Single PointIncremental Forming With the Ductile Fracture Criterion
,”
Proceedings of the 2007 InternationalManufacturing Science And Engineering Conference, MSEC 2007 Paper No. 31129.
2.
Duflou
,
J. R.
,
Lauwers
,
B.
,
Verbert
,
J.
,
Tunckol
,
Y.
, and
Baerdemaeker
,
H. D.
, 2005, “
Achievable Accuracy in Single Point Incremental Forming: Case Studies
,”
Proceedings of the 8th Esaform Conference on Material Forming
, Vol.,
2
, pp.
675
678
.
3.
Verbert
,
J.
,
Dulfou
,
J. R.
, and
Lauwers
,
B.
, 2007, “
Feature Based Approach for Increasing the Accuracy of the SPIF Process
,”
Key Eng. Mater.
,
344
, pp.
527
534
.
4.
Allwood
,
J. M.
,
Music
,
O.
,
Raithathna
,
A.
, and
Duncan
,
S. R.
, 2009, “
Closed-Loop Feedback Control of Product Properties in Flexible Metal Forming Processes With Mobile Tools
,”
CIRP Ann.
,
58
(
1
), pp.
287
290
.
5.
Allwood
,
J. M.
,
Braun
,
D.
, and
Music
,
O.
, 2010, “
The Effect of Partially Cut-Out Blanks on Geometric Accuracy in Incremental Sheet Forming
,”
J. Mater. Process. Technol.
,
210
, pp.
1501
1510
.
6.
Emmens
,
W. C.
, and
van den Boogard
,
A. H.
, 2009, “
An Overview of Stabilizing Deformation Mechanisms in Incremental Sheet Forming
,”
J. Mater. Process. Technol.
,
209
, pp.
3688
3695
.
7.
Jackson
,
K.
, and
Allwood
,
J.
, 2009, “
The Mechanics of Incremental Sheet Forming
,”
J. Mater. Process. Technol.
,
209
(
3
), pp.
1158
1174
.
8.
Otsu
,
M.
,
Matsuo
,
H.
,
Matsuda
,
M.
, and
Takashima
,
K.
, 2010, “
Friction Stir Incremental Forming of Aluminum Alloy Sheets
,”
Steel Research International
,
81
(9), pp.
942
925
.
9.
Jeswiet
,
J.
,
Micari
,
F.
,
Hirt
,
G.
,
Bramley
,
A.
,
Duflou
,
J.
, and
Allwood
,
J.
, 2005, “
Asymmetric Single Point Incremental Forming of Sheet Metal
,”
CIRP Ann.-Manuf. Technol.
,
54
(
2
), pp.
88
114
.
10.
Hussain
,
G.
,
Gao
,
L.
,
Hayat
,
N.
, and
Qijia
,
L.
, 2007, “
The Effect of Variation in the Curvature of Part on the Formability in Incremental Forming: An Experimental Investigation
,”
Int. J. Mach. Tools Manuf.
,
47
, pp.
2177
2181
.
11.
Filice
,
L.
,
Fratini
,
L.
, and
Micari
,
F.
, 2002, “
Analysis of Material Formability in Incremental Forming
,”
CIRP Ann.-Manuf. Technol.
,
51
(
1
), pp.
199
202
.
12.
Hussain
,
G.
,
Gao
,
L.
,
Hayat
,
N.
, and
Zirana
,
X.
, 2009, “
A New Formability Indicator in Single Point Incremental Forming
,”
J. Mater. Process. Technol.
,
209
, pp.
4237
4242
.
13.
Silva
,
M. B.
,
Skjoedt
,
M.
,
Atkins
,
A. G.
,
Bay
,
N.
, and
Martins
,
P. A. F.
, 2008, “
Single‐Point Incremental Forming and Formability-Failure Diagrams
,”
J. Strain Anal. Eng. Des.
,
43
(
1
), pp.
15
35
.
14.
Malhotra
,
R.
,
Huang
,
Y.
,
Xue
,
L.
,
Cao
,
J.
, and
Belytschko
,
T.
, 2010, “
An Investigation on the Accuracy of Numerical Simulations for Single Point Incremental Forming With Continuum Elements
,”
Proceedings of the 10th International Conference on Numerical Methods in Industrial Forming Processes
, Vol.,
1252
, pp.
221
227
.
15.
Yamashita
,
M.
,
Gotoh
,
M.
, and
Atsumi
,
S. Y.
, 2008, “
Numerical Simulation of Incremental Forming of Sheet Metal
,”
J. Mater. Process. Technol.
,
199
(
1–3
), pp.
163
172
.
16.
Henrard
,
C.
,
Bouffioux
,
C.
,
Duchene
,
L.
, and
Duflou
,
J. R.
, 2007, “
Validation of a New Finite Element for Incremental Forming Simulation Using a Dynamic Explicit Approach
,”
Key Eng. Mater.
,
344
, pp.
495
502
.
17.
Cerro
,
I.
,
Maidagan
,
E.
,
Arana
,
J.
,
Rivero
,
A.
, and
Rodríguez
,
P. P.
, 2006, “
Theoretical and Experimental Analysis of the Dieless Incremental Sheet Forming Process
,”
J. Mater. Process. Technol.
,
177
(
1–3
), pp.
404
408
.
18.
Meier
,
H.
,
Smukala
,
V.
,
Dewald
,
O.
, and
Zhang
,
J.
, 2007, “
Two Point Incremental Forming With Two Moving Forming Tools
,”
Key Eng. Mater.
,
344
, pp.
599
605
.
19.
Wang
,
Y.
,
Wu
,
W.
,
Huang
,
Y.
,
Reddy
,
N. V.
, and
Cao
,
J.
, 2009, “
Experimental and Numerical Analysis of Double Sided Incremental Forming
,”
Proceedings of the 2009 International Manufacturing Science and Engineering Conference
pp.
613
618
20.
Wang
,
Y.
,
Huang
,
Y.
,
Cao
,
J.
, and
Reddy
,
N. V.
, 2008, “
Experimental Study on a New Method of Double Sided Incremental Forming
,”
Proceedings of the 2008 International Manufacturing Science and Engineering Conference
,
MSEC
2008 Paper no. 72279.
21.
Cao
,
J.
,
Huang
,
Y.
,
Reddy
,
N. V.
,
Malhotra
,
R.
, and
Wang
,
Y.
, 2008, “
Incremental Sheet Metal Forming: Advances and Challenges
,”
International Conference on Technology of Plasticity (ICTP – 2008)
, September 7–11, Gyeongju, South Korea.
22.
Jesweit
,
J.
,
Micari
,
F.
,
Hirt
,
G.
,
Bramley
,
A.
,
Duflou
,
J.
, and
Allwood
,
J.
, 2005, “
Asymmetric Single Point Incremental Forming of Sheet Metal
,”
CIRP Ann.-Manuf. Technol.
,
54
(
2
), pp.
88
114
You do not currently have access to this content.