High cycle (>106 cycles) fatigue (HCF) behavior of thick thermal barrier coatings (TTBC’s) was examined for applied stresses near the compressive strength of the material. Test data were obtained on four coating systems: two base materials in the unsealed and CrO2 dip sealed conditions. Free standing tubular specimens were evaluated. The data show that compressive fatigue limits exist for the four coating systems at room temperature (RT) and sealing with CrO2 improves RT fatigue life. Test results also show the ratio of the peak cyclic stress, at 105 cycles, to ultimate compressive strength (UCS) of the Yttria Stabilized Zirconia (YSZ) tubular specimens approaches 0.90 at R = 0.6 (R = minimum/maximum compressive stress). Residual UCS increases were observed after fatigue run-outs at elevated temperatures (5 at 700°C and 1 at 400°C) for both YSZ and the cermet. Ratchetting with cyclic hardening was observed during fatigue with deformation occurring primarily in the initial portion of the high cycle fatigue life of the specimens.

Issue Section:
Technical Papers
Topics:
Fatigue, Plasmas (Ionized gases), Cycles, Cathode ray oscilloscopes, Coatings, Compressive strength, High cycle fatigue, Stress, Temperature, Cermets, Compressive stress, Deformation, Fatigue life, Fatigue limit, Hardening, Sealing (Process), Thermal barrier coatings
1.
Brink, Randolph C., 1989, “Material Property Evaluation of Thick Thermal Barrier Coating Systems,” ASME 89-ICE-13.
2.
Cruse
T. A.
,
Stewart
S. E.
, and
Ortiz
M.
,
1988
, “
Thermal Barrier Coating Life Prediction Model Development
,”
ASME Journal of Engineering for Gas Turbines and Power
, Vol.
110
, pp.
610
–
616
.
3.
Cruse, T. A., 1990, “Fatigue Testing of Plasma Sprayed Thermal Barrier Coatings Volume 2,” SwRI 06-1778-002, NASA NCC 3-89.
4.
DeMasi, J. T., Sheffler, K. D., and Ortiz, M., 1989, “Thermal Barrier Coating Life Prediction Model Development,” Phase I Final Report, NASA Contractor Report 182230.
5.
DeMasi-Marcin
J. T.
,
Sheffler
K. D.
, and
Bose
S.
,
1990
, “
Mechanisms of Degradation and Failure in a Plasma-Deposited Thermal Barrier Coating
,”
ASME Journal of Engineering for Gas Turbines and Power
, Vol.
112
, pp.
521
–
526
.
6.
Firestone
R. F.
,
Logan
W. R.
, and
Adams
J. W.
,
1982
, “
Creep of Plasma-Sprayed-ZrO2 Thermal-Barrier Coatings
,”
Ceramic Eng. Sci. Proc
, Vol.
3
, pp.
158
–
171
.
7.
Hirth
G.
, and
Tullis
J.
,
1989
, “
The Effects of Pressure and Porosity on the Micromechanics of the Brittle-Ductile Transition in Quartzite
,”
J. Geophys. Res.
, Vol.
94
, No.
17
, pp.
825
–
838
.
8.
Johnsen, B. P., Cruse, T. A., Miller, R. A., and Brindley, W. J., 1993, “Compressive Fatigue Behavior of a ZrO2-8wt%Y203 TBC—Status Report,” Proceedings of the Advanced Heat Engine Workshop, Monterey, CA, p. 11–41 to 11–47.
9.
Larson, H. J., and Brink, R. C, 1988, “Thick Thermal Barrier Coatings for Diesel Components—Task 2 Briefing,” NASA contract DEN3-332.
10.
McPherson
R.
,
1989
, “
A Review of Microstructure and Properties of Plasma Sprayed Ceramic Coatings
,”
Surface Coatings Tech.
, Vol.
39/40
, pp.
173
–
181
.
11.
Meier
S. M.
,
Nissley
D. M.
,
Sheffler
K. D.
, and
Cruse
T. A.
,
1992
, “
Thermal Barrier Coating Life Prediction Model Development
,”
ASME Journal of Engineering for Gas Turbines and Power
, Vol.
114
, pp.
258
–
263
.
12.
Suresh, S., Christman, T., and Bull, C, 1986, “Crack Initiation and Growth Under Far-Field Cyclic Compression: Theory, Experiments and Applications,” Small Fatigue Cracks, R. O. Ritchie and J. Lankford, eds., AIME, Warrendale, PA, pp. 513–540.
13.
Suresh
S.
, and
Brockenbrough
J. R.
,
1988
, “
Theory and Experiments of Fracture in Cyclic Compression: Single-Phase Ceramics, Transforming Ceramics, and Ceramic Composites
,”
Acta Metall.
, Vol.
36
, No.
6
, pp.
1455
–
1470
.
14.
Wesling, K. F., Socie, D. F., and Beardsley, B., 1993, “Cyclic Compression of Thick Thermal Barrier Coatings,” Submitted to The American Ceramic Society, Inc.
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