DOI QR코드

DOI QR Code

Evaluation of Degradation Characteristics of Thermal Barrier Coating on Gas Turbine Blades

  • Jung, Yongchan (Creative Future Technology Lab., KEPCO Research Institute, Korea Electric Power Corporation) ;
  • Kim, Mintae (Creative Future Technology Lab., KEPCO Research Institute, Korea Electric Power Corporation) ;
  • Lee, Juhyeung (Creative Future Technology Lab., KEPCO Research Institute, Korea Electric Power Corporation) ;
  • Ahn, Jamin (Materials Engineering, Korea University of Technology and Education) ;
  • Kim, Kihong (Materials Engineering, Korea University of Technology and Education)
  • 투고 : 2016.02.12
  • 심사 : 2016.03.15
  • 발행 : 2016.06.30

초록

In order to evaluate the lifespan of high-temperature parts with thermal barrier coating in gas turbines used for power generation, this study was performed on an 80 MW-class gas turbine exceeding 24 k equivalent operating hours. Degradation characteristics were evaluated by analyzing the YSZ (Yttria Stabilized Zirconia) top coat, which serves as the thermal barrier coating layer, the NiCrAlY bond coat, and interface layers. Microstructural analysis of the top, middle, and bottom sections showed that Thermal Growth Oxide (TGO) growth, Cr precipitate growth within the bond coat layer, and formation of diffusion layer occur actively in high-temperature sections. These microstructural changes were consistent with damaged areas of the thermal barrier coating layer observed at the surface of the used blade. The distribution of Cr precipitates within the bond coat layer, in addition to the thickness of TGO, is regarded as a key indicator in the evaluation of degradation characteristics.

키워드

참고문헌

  1. Yong Chan Jung, Tae Hee Lee and Ki Tae Kim, Eng. Fail. Anal. 32, 98-105 (2013). https://doi.org/10.1016/j.engfailanal.2013.03.006
  2. Min Tae Kim and Yong Chan Jung, Surf. Coat. Technol., 210, 166-175 (2012). https://doi.org/10.1016/j.surfcoat.2012.09.013
  3. Yong Chan Jung and Ki Tae Kim, Met. Mater. Int., 17, 279-282 (2011). https://doi.org/10.1007/s12540-011-0415-6
  4. Yong Chan Jung and Han Sub Chung, Met. Mater. Int., 16, 267-271 (2010). https://doi.org/10.1007/s12540-010-0416-x
  5. Aymeric Raffaitin, Fabrice Crabos, Eric Andrieu, Daniel Monceau, Surf. Coat. Technol., 201, 3829-3835 (2006). https://doi.org/10.1016/j.surfcoat.2006.07.256
  6. W.R. Chen, X. Wu, D. Dudzinski, P.C. Patnaik, Surf. Coat. Technol., 200, 5863-5868 (2006). https://doi.org/10.1016/j.surfcoat.2005.08.141
  7. B.G. Mendis, B. Tryon, T. M. Pollock, K. J. Hemker, Surf. Coat. Technol., 201, 3918-3925 (2006). https://doi.org/10.1016/j.surfcoat.2006.07.249
  8. G. G. Levi, E. Sommer, S. G. Terry, A. Catanoiu, Jour. American Ceramic Society, 86, 676-685 (2006).
  9. W. J. Quadakkers, V. Shemet, D. Sebold, R. Anton, E. Wessel, L. Singheiser, Surf. Coat. Technol., 199, 77-82 (2005). https://doi.org/10.1016/j.surfcoat.2004.11.038
  10. B. Wang, J. Gong, C. Sun, R.F. Huang, L.S. Wen, Mater. Sci. Eng., 357, 39-44 (2003). https://doi.org/10.1016/S0921-5093(03)00254-5
  11. Meiheng Li, Xiaofeng Sun, Wangyu Hu, Hengrong Guan, Materials Letters, 61, 5169-5172 (2007). https://doi.org/10.1016/j.matlet.2007.04.022
  12. C.S. Richard, G. Beranger, J.Lu, J.F. Flavenot, Surf. Coat. Technol., 82, 99-109 (1996). https://doi.org/10.1016/0257-8972(95)02640-1