Hostname: page-component-7479d7b7d-k7p5g Total loading time: 0 Render date: 2024-07-08T15:47:42.918Z Has data issue: false hasContentIssue false
  • English
  • Français

Near-Interface Crack Initiation in Thermal Barrier Coatings

Published online by Cambridge University Press:  10 February 2011

Z. Zhang ,
T. E. Bloomer ,
J. Kameda  and
S. Sakurai
Z. Zhang
Affiliation:
Ames Laboratory, Iowa State University, Ames, IA 50011, USA
T. E. Bloomer
Affiliation:
Ames Laboratory, Iowa State University, Ames, IA 50011, USA Presently, US Nuclear Regulatory Commission, Washington, D. C., 20555USA
J. Kameda
Affiliation:
Ames Laboratory, Iowa State University, Ames, IA 50011, USA
S. Sakurai
Affiliation:
Mechanical Engineering Research Laboratory, Hitachi Ltd., Hitachi 317, Japan
Get access

Abstract

The delamination behavior of thermal barrier coatings (TBC) in transition ducts of inservice used combusters has been characterized using a protruded four-point bending testing technique recently developed by the authors. A reinforced protruded TBC specimen allowed the formation of TBC cracks adjacent to the TBC/alumina interface in a similar mode to inservice TBC failure. Finite element stress analysis showed that a peak transverse stress appeared in a protruded TBC part away from the interface and a large principal tensile stress operated on planes inclined to the interface. It was found that the onset of near-interface TBC cracks in the protruded TBC specimen did not occur under the high transverse and principal tensile stresses. The critical local tensile stress for the onset of TBC cracks near the interface, estimated to be 127 MPa, was lower than that of the near-center TBC. The near-interface TBC cracking behavior in the protruded TBC tests is discussed in light of the residual stress distribution and stressed volume effect.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 586: Symposium M – Interfacial Engineering for Optimized Properties II , 1999 , 279
Copyright
Copyright © Materials Research Society 2000

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. DeMasi, J. T., Sheffler, K. D., and Ortiz, M., NASA Contract Report-182230, 1989.Google Scholar
2. Meier, S. M., Nissley, D. M., and Sheffler, K. D., NASA Contract Report-189111, 1991.Google Scholar
3. Jordan, E. H., Gell, M., Pease, D. M., Shaw, L., Clarke, D. R., Gupta, V., Barber, B. and Vaidyanathan, K., ASME Turbo Expo'97 (American Society of Mechanical Engineers, NewYork, 1997) GT-97–363.Google Scholar
4. Charalambides, P. G., Lund, J., Evans, A. G. and McMeeking, R. M., J Appl. Mech., 56, 77(1989).Google Scholar
5. ASTM Standard C633–79 C, American Society of Testing Materials, Philadelphia, 1979.Google Scholar
6. Johnson, C. A., Private Communication, 1996.Google Scholar
7. Zhang, Z., Bloomer, T. E., Kameda, J. and Sakurai, S., ASME Turbo'99 (American Society of Mechanical Engineers, New York, NY, 1999) GT-99–380.Google Scholar
8. Zhang, Z., Bloomer, T. E. and Kameda, J., Contract Progress Report, Ames Laboratory,1998.Google Scholar
9. Scardi, P., Leoni, M., Bertini, L., and Bertamini, L., Surf. Coat. Tech., 94–95, 82 (1997).10.1016/S0257-8972(97)00482-9Google Scholar
10. Qian, G., Nakamura, T., Berndt, C. C. and Leigh, S. H., Acta Mater., 45, 1767 (1997).Google Scholar
11. Weibull, W., J. Appl. Mech., 18, 293 (1951).Google Scholar
12. Richardson, W., in Modem Ceramic Engineering: Properties, Processing and Use in Design, (M. Dekker, New York, 1982).Google Scholar