Share This Article:

High Temperature Sintering and Oxidation Behavior in Plasma Sprayed TBCs [Single Splat Studies] Paper 1—Role of Heat Treatment Variations

Abstract Full-Text HTML Download Download as PDF (Size:4007KB) PP. 106-115
DOI: 10.4236/jsemat.2013.31A015    3,647 Downloads   6,452 Views  

ABSTRACT

The TBC system is examined with regards to its response to thermal exposure at high temperature. It has been established before that the thermally grown oxide (TGO) layer that forms upon bond coat oxidation is the key factor determining the performance of the TBC system and/or its failure. However, characteristics of TGO growth, bond coat rumpling, principles governing failure of TBC systems and the various failure mechanisms have been studied extensively in case of just super alloy with bond coat or with thick top coating. In this study super alloy/bond coat system with single splats of YSZ instead of thick topcoat is analyzed in order to scrutinize the effect on the first layer of splats during thermal exposure. The splats with microcracks are the building blocks of the top coat. The most important aspect of this layer is the inherent inter-splat and intra-splat porosity which undergoes sintering during thermal exposure. The interactions between the YSZ splats and the evolving TGO is directly linked to the presence or absence of bond coat oxidation. Therefore the high temperature behavior of this system is analyzed with variations in heat treatment involving, temperature, duration and environment of thermal exposure.

Conflicts of Interest

The authors declare no conflicts of interest.

Cite this paper

S. Deshpande, "High Temperature Sintering and Oxidation Behavior in Plasma Sprayed TBCs [Single Splat Studies] Paper 1—Role of Heat Treatment Variations," Journal of Surface Engineered Materials and Advanced Technology, Vol. 3 No. 1A, 2013, pp. 106-115. doi: 10.4236/jsemat.2013.31A015.

References

[1] P. S. Mohanty, “Challenges in Thermal Spraying of Refractory Materials,” Surface Engineering, Vol. 21, No. 1, 2005, pp. 1-4. doi:10.1179/174329405X36691
[2] A. G. Evans, “Thermal Barrier Coatings: Workshop Summary,” TBC Workshop, Irsee, 17-22 August 2003, pp. 17-22.
[3] A. N. Khan and J. Lu, “Behavior of Air Plasma Sprayed Thermal Barrier Coatings, Subject to Intense Thermal Cycling,” Surface and Coatings Technology, Vol. 166, No. 1, 2003, pp. 37-43. doi:10.1016/S0257-8972(02)00740-5
[4] T. Xu, M. Y. He and A. G. Evans, “A Numerical Assessment of the durability of Thermal Barrier Systems That Fail by Ratcheting of the Thermally Grown Oxide,” Acta Materialia, Vol. 51, No. 13, 2003, pp. 3807-3820. doi:10.1016/S1359-6454(03)00194-0
[5] A. M. Karlsson, J. W. Hutchinson and A. G. Evans, “The Displacement of the Thermally Grown Oxide in Thermal Barrier Systems upon Thermal Cycling,” Materials Science and Engineering, Vol. 351, No. 1-2, 2003, pp. 244-257. doi:10.1016/S0921-5093(02)00843-2
[6] M. Y. He, A. G. Evans and J. W. Hutchinson, “The Ratcheting of Compressed Thermally Grown Thin Films on Ductile Substrates,” Acta Materialia, Vol. 48, No. 10, 2000, pp. 2593-2601. doi:10.1016/S1359-6454(00)00053-7
[7] D. R. Mumm, A. G. Evans and I. T. Spitsberg, “Characterization of a Cyclic Displacement Instability for a Thermally Grown Oxide in a Thermal Barrier System,” Acta Materialia, Vol. 49, No. 12, 2001, pp. 2329-2340. doi:10.1016/S1359-6454(01)00071-4
[8] A. G. Evans, D. R. Mumm, J. W. Hutchinson, G. H. Meier and F. S. Pettit, “Mechanisms Controlling the Durability of Thermal Barrier Coatings,” Progress in Materials Science, Vol. 46, No. 5, 2001, pp. 505-553. doi:10.1016/S0079-6425(00)00020-7
[9] R. Panat, S. Zhang and K. J. Hsia, “Bond Coat Surface Rumpling in Thermal Barrier Coatings,” Acta Materialia, Vol. 51, No. 1, 2003, pp. 239-249. doi:10.1016/S1359-6454(02)00395-6
[10] A. M. Karlsson and A. G. Evans, “A Numerical Model for the Cyclic Instability of Thermally Grown Oxides in Thermal Barrier Systems,” Acta Materialia, Vol. 49, No. 10, 2001, pp. 1793-1804. doi:10.1016/S1359-6454(01)00073-8
[11] A. Rabiei and A. G. Evans, “Failure Mechanisms Associated with the Thermally Grown Oxide in Plasma Sprayed Thermal Barrier Coatings,” Acta Materialia, Vol. 48, No. 15, 2000, pp. 3963-3976. doi:10.1016/S1359-6454(00)00171-3
[12] E. A. G. Shillington and D. R. Clarke, “Spalling Failure of a Thermal Barrier Coating Associated with Aluminum Depletion in the Bond-Coat,” Acta Materialia, Vol. 47, No. 4, 1999, pp. 1297-1305. doi:10.1016/S1359-6454(98)00407-8
[13] J. Thornton, D. Cookson and E. Prescott, “The Measurement of Strains within the Bulk of Aged and As-Sprayed Thermal Barrier Coatings Using Synchrotron Radiation,” Surface and Coatings Technology, Vol. 120-121, 1999, 96-102. doi:10.1016/S0257-8972(99)00340-0

  
comments powered by Disqus

Copyright © 2018 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.