Thermal Fatigue Damage Evaluation of EB-PVD TBC Specimens - Its Potential and Problems

Abstract:

Thermal fatigue damage evolution behavior in thermal barrier coatings (TBCs) was studied, by employing the originally designed two dimensional ring-shape TBC specimen. The TBC specimen consisted of Ni-based superalloy IN738LC substrate, bond coat, and 8 wt.% Y2O3-stabilized ZrO2 (YSZ) top coat. The top coat was fabricated by electron-beam physical vapor deposition (EB-PVD) method with 250 micron-meters in thickness. Three kinds of MCrAlY bond coat alloys were specified as an experimental variable. Through the work, special attention was paid not only to the failure life of TBC specimen, but also to the underlying failure mechanisms. Some problems have been also pointed out, on feeding back these experimental findings to engineering applications.

• Periodical: Materials Science Forum (Volumes 631-632)
• Pages: 91-96
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.631-632.91
• Online since: October 2009
• Authors: Masakazu Okazaki, S. Yamagishi, Motoki Sakaguchi, T. Okamura
• Keywords: Bond Coat, EB-PVD, Spalling, Thermal Barrier Coating (TBC), Thermal Fatigue, Thermally Grown Oxide (TGO)

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