A method of simulating the age forming of initially flat panels is proposed. It conceptually divides the process into three phases (loading, aging, and unloading) and simulates each phase separately. Some sample simulations are presented for 7075 aluminum alloy based on a simplified version of the general procedure (linear loading and unloading, nonlinear aging). The results of these simulations are used to illustrate several aspects of the predictions. An interesting finding is that the part shape and tool shape are geometrically similar in two important special cases.

1.
Bodner
S. R.
, and
Partom
Y.
,
1975
, “
Constitutive Equations for Elastic-Viscoplastic Strain-Hardening Materials
,”
ASME Journal of Applied Mechanics
, Vol.
42
, pp.
385
389
.
2.
Bodner
S. R.
, and
Merzer
A.
,
1978
, “
Viscoplastic Constitutive Equations for Copper with Strain Rate History and Temperature Effects
,”
ASME JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY
, Vol.
100
, pp.
388
394
.
3.
Cook, R. D., Malkus, D. S., and Plesha, M. E., 1989, Concepts and Applications of Finite Element Analysis, Wiley, New York.
4.
Freed
A. D.
, and
Walker
K. P.
,
1990
, “
Steady-State and Transient Zener Parameters in Viscoplasticity: Drag Strength Versus Yield Strength
,”
Applied Mechanics Reviews
, Vol.
43
, pp.
S328–S337
S328–S337
.
5.
Freed
A. D.
, and
Walker
K. P.
,
1995
, “
Viscoplastic Model Development with an Eye Toward Characterization
,”
ASME JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY
, Vol.
117
, pp.
8
13
.
6.
Foroudastan
S.
,
Peddieson
J.
, and
Holman
M. C.
,
1992
, “
Application of a Unified Viscoplastic Model to Simulation of Autoclave Age Forming
,”
ASME JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY
, Vol.
114
, pp.
71
76
.
7.
Gardiner
F. J.
,
1957
, “
The Spring Back of Metals
,”
Trans. ASME
, Vol.
79
, pp.
1
9
.
8.
Hart
E. W.
,
1976
, “
Constitutive Relations for the Nonelastic Deformation of Metals
,”
ASME JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY
, Vol.
98
, pp.
193
202
.
9.
Holman
M. C.
,
1989
, “
Autoclave Age Forming Large Aluminum Aircraft Panels
,”
Journal of Mechanical Working Technology
, Vol.
20
, pp.
477
488
.
10.
Hughes
T. J. R.
, and
Cohen
M.
,
1978
, “
The Heterosis Finite Element for Plate Bending
,”
Computers and Structures
, Vol.
9
, pp.
445
450
.
11.
James
G. H.
,
Imbrie
P. K.
,
Hill
P. S.
,
Allen
D. H.
, and
Haisler
W. E.
,
1987
, “
An Experimental Comparison of Several Current Viscoplastic Constitutive Models at Elevated Temperatures
,”
ASME JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY
, Vol.
109
, pp.
130
139
.
12.
Johnson
W.
, and
Yu
T. X.
,
1981
a, “
Springback After the Biaxial Elastic-Plastic Pure Bending of a Rectangular Plate-I
,”
International Journal of Mechanical Sciences
, Vol.
23
, pp.
619
630
.
13.
Johnson
W.
, and
Yu
T. X.
,
1981
b, “
On Springback After the Pure Bending of Beams and Plates of Elastic Work-Hardening Materials-III
,”
International Journal of Mechanical Sciences
, Vol.
23
, pp.
687
695
.
14.
Karafilis
A. P.
, and
Boyce
M. C.
,
1992
, “
Tooling Design in Sheet Metal Forming Using Springback Calculations
,”
International Journal of Mechanical Sciences
, Vol.
34
, pp.
113
131
.
15.
Miller
A. K.
,
1976
a, “
An Inelastic Constitutive Model for Monotonic, Cyclic, and Creep Deformations, Part I
,”
ASME JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY
, Vol.
98
, pp.
97
105
.
16.
Miller
A. K.
,
1976
b, “
An Inelastic Constitutive Model for Monotonic, Cyclic, and Creep Deformations, Part II
,”
ASME JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY
, Vol.
98
, pp.
106
113
.
17.
Miller
A. K.
,
1980
, “
Modelling of Cyclic Plasticity With Unified Constitutive Equations: Improvements in Simulating Normal and Anomalous Bauschinger Effects
,”
ASME JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY
, Vol.
102
, pp.
215
222
.
18.
Miller
A. K.
, and
Shih
C. F.
,
1977
, “
An Improved Method for Numerical Integration of Constitutive Equations of the Work Hardening Recovery Type
,”
ASME JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY
, Vol.
99
, pp.
275
277
.
19.
Miller
A. K.
, and
Sherby
O. D.
,
1978
, “
A Simplified Phenomenological Model for Non-Elastic Deformation: Predictions of Pure Aluminum Behavior and Incorporation of Solute Strengthening Effects
,”
Acta Metallurgica
, Vol.
26
, pp.
289
304
.
20.
Peddieson
J.
, and
Buchanan
G. R.
,
1990
, “
Mathematical Modeling of an Age-Forming Process
,”
Mathematical and Computer Modeling
, Vol.
14
, pp.
1057
1060
.
21.
Sallah
M.
,
Peddieson
J.
, and
Foroudastan
S.
,
1991
, “
A Mathematical Model of Autoclave Age Forming
,”
Journal of Materials Processing Technology
, Vol.
28
, pp.
211
219
.
22.
Senseny
P. E.
,
Brodsky
N. S.
, and
DeVries
K. L.
,
1993
, “
Parameter Evaluation for a Unified Constitutive Model
,”
ASME JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY
, Vol.
115
, pp.
157
162
.
23.
Senseny
P. E.
, and
Fossum
A. F.
,
1995
, “
On Testing Requirements for Viscoplastic Constitutive Parameter Estimation
,”
ASME JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY
, Vol.
117
, pp.
151
156
.
24.
Stouffer
D. C.
, and
Bodner
S. R.
,
1979
, “
A Constitutive Model for the Deformation Induced Anisotropic Plastic Flow of Metals
,”
International Journal of Engineering Science
, Vol.
17
, pp.
757
764
.
25.
Walker, K. P., and Wilson, D. A., 1983, “Constitutive Modeling for Engine Materials,” United Technologies Pratt and Whitney Report FR-17911.
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