Abstract
High temperature behavior of air plasma sprayed (APS) thermal barrier coatings (TBC) was investigated in this study by electrochemical impedance spectroscopy (EIS). Scanning electron microscope (SEM) was used to examine cross-sectional morphology of exposed TBC. It was found that characteristic EIS spectra were obtained effectively to differentiate variant post-exposed TBC such as isothermal oxidation and cyclic oxidation. In addition, the type and length of high temperature exposure were qualitatively discernible from the EIS data. A model of an EIS alternative current (AC) equivalent circuit was proposed quantitatively to relate the EIS parameters to the morphological properties of the exposed TBC and functional relationships have been established between them. From the results, EIS has been identified capable of monitoring the microstructure of post-exposed TBC and evaluating TBC damage.
Similar content being viewed by others
References
S. Q. Nusier, G. M. Newaz and Z. A. Chaudhury, International Journal of Solids and Structures 37 (2000), pp. 2495–2506
M. J. Stiger, N. M. Yanar, F. S. Pettit and G. H. Meier, Elevated Temperature Coatings: Science and Technology III, ed by J. M. Hampikian and N. B. Dahotre (A Publication of TMS), (1999) pp. 51–66.
Richard Croce, Pierre Calmon and Luc Paradis, Ultrasonics, 38, pp. 537–541 (2000).
D. Bates, G. Smith, D. Lu and J. Hewitt, Composites: Part B 31, pp. 175–185, (2000).
Z. A. Chaudhury, G. M. Newaz, S. Q. Nusier and T. Ahmed, Materials Science and Engineering A 231, pp. 34–41 (1997).
S. Alaruri, T. Bonsett, A. Brewington, E. McPheeters and M. Wilson, Optics and Lasers in Engineering, 31, No. 5, May (1999), pp. 1345–1351.
R. J. Christensen, D. M. Lipkin and D. R. Clarke, Applied Physics Letter, 69 (24), 9 December (1996), pp. 3754–3756.
J. Zhang, D. Tamboli and V. Desai, manuscript for Symposium M, Thermal Barrier Coating, 2000 MRS Fall Meeting, Boston, Massachusetts, November 27-December 2, (2000).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Zhang, J., Desai, V. Post-Exposure Evaluation of Thermal Barrier Coatings by Electrochemical Impedance Spectroscopy. MRS Online Proceedings Library 645, 921 (2000). https://doi.org/10.1557/PROC-645-M9.2.1
Published:
DOI: https://doi.org/10.1557/PROC-645-M9.2.1