A continuum damage mechanics (CDM) based viscoplastic constitutive model is established in this study to describe the fully coupling of creep and fatigue behavior. The most significant improvement is the introduction of a continuum damage variable into the constitutive equations, instead of considering creep damage and fatigue damage separately. The CDM-based viscoplastic constitutive material model is implemented using a user-defined subroutine (UMAT). A standard specimen is used for carrying out uniaxial creep, fatigue, and creep–fatigue interaction tests to validate the material model. In addition, to further demonstrate the capability of the material model to predict the complex material behavior, a complex strain-control loading test is performed to validate the material model. The simulated and measured results are in good agreement at different temperatures and loadings, in particular for rapid cyclic softening behavior following crack initiation and propagation.

References

1.
Remy
,
L.
,
Szmytka
,
F.
, and
Bucher
,
L.
,
2013
, “
Constitutive Models for BCC Engineering Iron Alloys Exposed to Thermal-Mechanical Fatigue
,”
Int. J. Fatigue
,
53
, pp.
2
14
.
2.
Abdullah
,
A. S.
,
2012
, “
Cyclic Plasticity and Creep of Power Plant Materials
,” Ph.D. thesis, University of Nottingham, Nottingham, UK.
3.
Ringel
,
M.
,
Roos
,
E.
,
Maile
,
K.
, and
Klenk
,
A.
,
2005
, “
Constitutive Equations of Adapted Complexity for High Temperature Loading
,”
ECCC Creep Conference
, London, Sept. 12–14, pp.
638
648
.
4.
Chaboche
,
J. L.
, and
Nouailhas
,
D.
,
1989
, “
A Unified Constitutive Model for Cyclic Viscoplasticity and Its Applications to Various Stainless Steels
,”
ASME J. Eng. Mater. Technol.
,
111
(
4
), pp.
424
430
.
5.
Wang
,
W. Z.
,
Buhl
,
P.
, and
Klenk
,
A.
,
2015
, “
A Unified Viscoplastic Constitutive Model With Damage for Multi-Axial Creep-Fatigue Loading
,”
Int. J. Damage Mech.
,
24
(
3
), pp.
363
382
.
6.
Lemaitre
,
J.
, and
Chaboche
,
J. L.
,
1990
,
Mechanics of Solid Materials
,
Cambridge University Press
,
Cambridge, UK
.
7.
Dunne
,
F. P. E.
,
Makin
,
J.
, and
Hayhurst
,
D. R.
,
1992
, “
Automated Procedures for the Determination of High Temperature Viscoplastic Damage Constitutive Equations
,”
Proc. R. Soc. London, A
,
437
(
1901
), pp.
527
544
.
8.
Dunne
,
F. P. E.
, and
Hayhurst
,
D. R.
,
1992
, “
Modelling of Combined High-Temperature Creep and Cyclic Plasticity in Components Using Continuum Damage Mechanics
,”
Proc. R. Soc. London, A
,
437
(
1901
), pp.
545
566
.
9.
Lemaitre
,
J.
,
1996
, “
Phenomenological Aspects of Damage
,”
A Course on Damage Mechanics
, 2nd ed.,
Springer
,
Berlin
, pp.
1
17
.
10.
Kachanov
,
L. M.
,
1986
,
Introduction to Continuum Damage Mechanics
,
Martinus Nijhoff, Dordrecht
,
The Netherlands
.
11.
Jesus
,
A. M. P.
,
Ribeiro
,
A. S.
, and
Fernandes
,
A. A.
,
2005
, “
Finite Element Modeling of Fatigue Damage Using a Continuum Damage Mechanics Approach
,”
ASME J. Pressure Vessel Technol.
,
127
(
2
), pp.
157
164
.
12.
Lemaitre
,
J.
, and
Desmorat
,
R.
,
2005
, Engineering Damage Mechanics: Ductile, Creep, Fatigue and Brittle Failures,
Springer-Verlag
,
Berlin
.
13.
Mashayekhi
,
M.
,
Taghipour
,
A.
,
Askari
,
A.
, and
Farzin
,
M.
,
2012
, “
Continuum Damage Mechanics Application in Low-Cycle Thermal Fatigue
,”
Int. J. Damage Mech.
,
22
(
2
), pp.
285
300
14.
Ambroziak
,
A.
,
2005
, “
Numerical Modeling of Elasto-Viscoplastic Chaboche Constitutive Equations Using MSC.MARC
,”
Task Q.
,
9
(
2
), pp.
157
166
.
15.
Chaboche
,
J. L.
,
1989
, “
Constitutive Equations for Cyclic Plasticity and Cyclic Viscoplasticity
,”
Int. J. Plast.
,
5
(
3
), pp.
247
302
.
16.
Ambroziak
,
A.
, and
Klosowski
,
P.
,
2007
, “
The Elasto-Viscoplastic Chaboche Model
,”
Task Q.
,
10
(
1
), pp.
49
61
.
17.
Chaboche
,
J. L.
,
2008
, “
A Review of Some Plasticity and Viscoplasticity Constitutive Theories
,”
Int. J. Plast.
,
24
(
10
), pp.
1642
1693
.
18.
Ohno
,
N.
, and
Wang
,
J. D.
,
1993
, “
Kinematic Hardening Rules With Critical State of Dynamic Recovery—Part I: Formulations and Basic Features for Ratcheting Behavior
,”
Int. J. Plast.
,
9
(
3
), pp.
375
390
.
19.
Jing
,
J. P.
,
Meng
,
G.
,
Sun
,
Y.
, and
Xia
,
S. B.
,
2003
, “
An Effective Continuum Damage Mechanics Model for Creep–Fatigue Life Assessment of a Steam Turbine Rotor
,”
Int. J. Pressure Vessels Piping
,
80
(
6
), pp.
389
396
.
20.
Lemaitre
,
J.
,
1984
, “
How to Use Damage Mechanics
,”
Nucl. Eng. Des.
,
80
(
2
), pp.
233
245
.
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