A modified experimental method using digital image correlation (DIC), a noncontact optical method for measuring full-field displacements and strains, is used to interrogate accumulated fatigue damage for low and high cycle fatigue at continuum scales. Previous energy-based fatigue life prediction methods have shown that cyclic strain energy dissipated during fatigue acts as a key damage parameter for accurate determination of total and remaining fatigue life. DIC enables the collection of accurate strain energy measurements or damaging energy of complex geometries that would otherwise be exceedingly difficult and time consuming using traditional strain measurement techniques. Thus, the use of DIC to obtain strain energy measurements of gas turbine engine (GTE) components is highly advantageous for energy-based fatigue life prediction methods. Presented in this study is the experimental characterization of the cyclic strain energy dissipation as a means of predicting fatigue performance and assessment of damage progression of Aluminum 6061 subjected to fully reversed axial fatigue loading utilizing DIC. Validation of total and cyclic strain energy dissipation DIC measurements is accomplished with the simultaneous use of axial extensometery for direct comparison and implementation to strain energy-based life prediction methods.

References

References
1.
Findlay
,
S. J.
, and
Harrison
,
N. D.
,
2002
, “
Why Aircraft Fail
,”
Mater. Today
,
5
(
11
), pp.
18
25
.
2.
Jasper
,
T.
,
1923
, “
The Value of the Energy Relation in Testing of Ferrous Metals at Varying Ranges of Stress and at Intermediate High Temperatures
,”
London, Edinburgh Dublin Philos. Mag. J. Sci.
,
46
(
274
), pp.
609
627
.
3.
Enomoto
,
N.
,
1955
,
On Fatigue Tests Under Progressive Stress
, Vol.
55
,
ASTM
, West Conshohocken, PA, pp.
903
917
.
4.
Feltner
,
C.
, and
Morrow
,
J.
,
1961
, “
Microplastic Strain Hysteresis Energy as a Criterion for Fatigue Fracture
,”
ASME J. Basic Eng.
,
83
(
1
), pp.
15
22
.
5.
Stowell
,
E. Z.
,
1966
, “
Energy Criterion for Fatigue
,”
Nucl. Eng. Des.
,
3
(
1
), pp.
32
40
.
6.
Scott-Emuakpor
,
O.
,
Shen
,
M. H. H.
,
George
,
T.
,
Cross
,
C. J.
, and
Calcaterra
,
J.
,
2007
, “
Development of an Improved High Cycle Fatigue Criterion
,”
ASME J. Eng. Gas Turbines Power
,
129
(
1
), pp.
162
169
.
7.
Scott-Emuakpor
,
O. E.
,
Shen
,
H.
,
George
,
T.
, and
Cross
,
C.
,
2008
, “
An Energy-Based Uniaxial Fatigue Life Prediction Method for Commonly Used Gas Turbine Engine Materials
,”
ASME J. Eng. Gas Turbines Power
,
130
(
6
), p.
062504
.
8.
Scott-Emuakpor
,
O.
,
George
,
T.
,
Cross
,
C.
, and
Shen
,
M. H. H.
,
2010
, “
Hysteresis-Loop Representation for Strain Energy Calculation and Fatigue Assessment
,”
J. Strain Anal. Eng. Des.
,
45
(
4
), pp.
275
282
.
9.
Wertz
,
J.
,
Shen
,
M. H. H.
,
Scott-Emuakpor
,
O.
,
George
,
T.
, and
Cross
,
C.
,
2012
, “
An Energy-Based Torsional-Shear Fatigue Lifing Method
,”
Exp. Mech.
,
52
(
7
), pp.
705
715
.
10.
Wertz
,
J.
,
Shen
,
M. H. H.
,
Scott-Emuakpor
,
O.
,
George
,
T.
, and
Cross
,
C.
,
2011
, “
An Energy-Based Axial Isothermal-Mechanical Fatigue Lifing Procedure
,”
ASME J. Eng. Gas Turbines Power
,
134
(
2
), p.
024502
.
11.
Sutton
,
M. A.
,
Wolters
,
W. J.
,
Peters
,
W. H.
,
Ranson
,
W. F.
, and
McNeill
,
S. R.
,
1983
, “
Determination of Displacements Using an Improved Digital Correlation Method
,”
Exp. Mech.
,
1
(
3
), pp.
133
139
.
12.
Chu
,
T. C.
,
Ranson
,
W. F.
,
Sutton
,
M. A.
, and
Peters
,
W. H.
,
1985
, “
Applications of Digital Image Correlation Techniques to Experimental Mechanics
,”
Exp. Mech.
,
25
(
3
), pp.
232
244
.
13.
Sutton
,
M. A.
,
Cheng
,
M.
,
Peters
,
W. H.
,
Chao
,
Y. J.
, and
McNeill
,
S. R.
,
1986
, “
Application of an Optimized Digital Correlation Method to Planar Deformation Analysis
,”
Image Vision Comput.
,
4
(
3
), pp.
143
150
.
14.
Yoneyama
,
S.
,
Kitagawa
,
A.
,
Iwata
,
S.
,
Tani
,
K.
, and
Kikuta
,
H.
,
2007
, “
Bridge Deflection Measurement Using Digital Image Correlation
,”
Exp. Tech.
,
31
(
1
), pp.
34
40
.
15.
Stinville
,
J. C.
,
Echlin
,
M. P.
,
Texier
,
D.
,
Bridier
,
F.
,
Bocher
,
P.
, and
Pollock
,
T. M.
,
2016
, “
Sub-Grain Scale Digital Image Correlation by Electron Microscopy for Polycrystalline Materials During Elastic and Plastic Deformation
,”
Exp. Mech.
,
56
(
2
), pp.
197
216
.
16.
Holyrcoss
,
C.
,
Shen
,
M.-H. H.
,
Scott-Emuakpor
,
O. E.
, and
George
,
T.
,
2015
, “
In Situ Study of Static and Dynaic Strain Energy Density at Notch Roots and Fatigue Cracks Using Digital Image Correlation
” AIAA 2016–0734.
17.
ASTM
,
2012
, “
Standard Test Method for Strain-Controlled Fatigue Testing
,” ASTM International, West Conshohocken, PA, Standard No. E606/E606M–12.
18.
Correlated Solutions
,
2010
, “
Vic-Gauge 2D Testing Fundamentals
,” CSI Application Note AN-722.
19.
Shen
,
M.-H. H.
, and
Akanda
,
S.
,
2014
, “
An Energy-Based Framework to Determine the Fatigue Strength and Fatigue Ductility Parameters for LCF/HCF Life Assessment of Turbine Materials
,”
ASME
Paper No. GT2014-26149.
20.
Shen
,
M.-H. H.
, and
Akanda
,
S. R.
,
2015
, “
A Modified Closed Form Energy Based Framework for Fatigue Life Assessment for Aluminum 6061-T6—Damaging Energy Approach
,”
ASME J. Eng. Mater. Technol.
,
137
(
2
), p.
021008
.
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