Damage Evaluation of TBC by Rapid Thermal Cycling Test Utilizing a Laser Irradiation

Abstract:

Thermal barrier coating (TBC) is deposited onto the gas turbine blade surface in order to protect the substrate from high-temperature combustion gas. Cracks and delamination of the ceramic coating which come from high heat flux loading are serious problem in TBC. In this study, the rapid thermal cycling device utilizing laser irradiation was developed. It was then investigated how the damage progresses in the ceramic coating exposed to cyclic rapid thermal loading. As a result, a sintering layer was formed in the surface of the ceramic coating, although such phenomenon was not recognized in TBC sample tested by the conventional thermal cycling test using an electric furnace. It was also revealed from the cross-sectional observation that the vertical crack was initiated at the surface of TBC and propagated into sintering layer. Finally, mechanical factors of those damages from finite element analysis using the TBC model including sintering progress was discussed

• Periodical: Key Engineering Materials (Volume 827)
• Pages: 361-366
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.827.361
• Online since: December 2019
• Authors: Yusuke Hayashi, Kento Suzuki, Masayuki Arai, Kiyohiro Ito, Tsuyoshi Higuchi, Yuka Suzuki, Tatsuo Suidzu
• Keywords: Finite Element Analysis, Gas Turbine, Laser Irradiation, Thermal Barrier Coatings

References

[1] D.R. Clark and S.R. Phillpot, Materials Today, June 2005, pp.22-29.

[2] M. Bartsch et. al., International Journal of Fatigue, Vol. 30 (2008), pp.211-218.

[3] A. Thibblin et al., Surface and Coatings Technology, Vol. 350, No. 25 (2018), pp.1-11.

[4] Y. Ito et al., Journal of the Society of Materials Science, Japan, Vol. 47, No.7 (1998), pp.672-677 (in Japanese).