Abstract
High-temperature oxidation and hot corrosion tests were conducted at 800 to 1100 °C under isothermal and thermal-cycle conditions for two kinds of thermal barrier coating (TBC) systems with different compositions of ceramic top coat: Y2O3-stabiIized zirconia (YSZ) and CaO-SiO2-ZrO2 (C2S-CZ). Qualitative and quantitative failure analyses were carried out to clarify the failure mechanisms of TBC systems. In high-temperature oxidation up to 1100 °C, the YSZ-TBC system was subjected more easily to spalling of the ceramic top coat. This is attributed to the localized oxidation along the ceramic top coat/metallic (NiCrAlY) bond coat interface, as compared with the case of the C2S-CZ-TBC system. Thus, the most significant oxidation damage resulted in the YSZ system under the thermal-cycle condition. On the other hand, for hot corrosion by Na2SO4-NaCI molten salt up to 1000 °C, the C2S-CZ system was more reactive with the molten salt to form a new phase layer composed of both the metallic bond coat constituents, such as aluminum and chromium, and corrosive species such as oxygen at the inner region of the ceramic top coat. Furthermore, effects of both the heat treatment, in particular the atmosphere after plasma spraying, and the chromium content of the bond coat were investigated for each coating system.
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References
G.W. Meetham, Coating Requirements in Gas Turbine Engines,J. Vac. Sci. Technol, Vol A3 (No. 6), 1985, p 2509–2515
H. Takeda,Ceramic Coating, H. Takeda, Ed., Nikkan-Kogyo-Shim- bunsya, Tokyo, 1988, p 179-199 (in Japanese)
S.R.J. Saunders and J.R. Nicholls, Coatings and Surface Treatments for High Temperature Oxidation Resistance,Mater. Sci. Technol., Vol 5, 1989, p 780–798
S. Sodeoka, M. Suzuki, T. Inoue, Y. Ono, and K. Ueno, Plasma Spray under Controlled Atmosphere up to 300 kPa,Proc. ITSC, 95, A. Ohmori, Ed., High Temp. Soc. Japan, Vol 1, 1995, p 283–288
P.E. Hodge, R. A. Miller, and M.A. Gedwill, Evaluation of the Hot Cor- rosion Behavior of Thermal Barrier Coatings,Thin Solid Films, Vol 73, 1990, p 447–453
R. Tanaka and O. Miyagawa, Test Methods for Fuel Oil Ash Corrosion of Heat Resisting Alloys,Trans. ASME-JEMT, Vol 10, 1973, p 322- 329
M. Yoshiba, O. Miyagawa, H. Mizuno, and H. Fujishiro, Effect of Envi- ronmental Factors on the Creep Rupture Properties of a Nickel-Base Superalloy Subjected to Hot Corrosion,Trans. Japan Inst. Metals, Vol 29, 1988, p 26–41
K. Wada, M. Yoshiba, and Y. Harada, Failure and Strength Degradation in Hot Corrosion Environment of Various Nickel-Base Superal- loy/Coating Systems by Plasma Spraying,Rep. 123rd Committee of Japan Soc. Promotion Sci., Vol 32, 1991, p 405–425 (in Japanese)
M. Yoshiba, Effect of Hot Corrosion on the Mechanical Perfor- mances of Superalloys and Coating Systems,Corros. Sci., Vol 35, 1993, p 1115–1124
M. Yoshiba, T. Aranami, H. Taira, and Y. Harada, Failure Analysis of Some Plasma Spray Coated Superalloy Systems Subjected to the Syn- ergistic High Temperature Damage in Actual Gas Turbine or in Labora- tory,Proc. ITSC, 95, A. Ohmori, Ed., High Temp. Soc. Japan, Vol 1, 1995, p 89–94
B.C. Wu and E. Chang, Thermal Cyclic Response of Yttria-Stabilized Zirconia/CoNiCrAlY Thermal Barrier Coatings,Thin Solid Films, Vol 172, 1989, p 185–196
S. Stecura, Effects of Yttrium, Aluminum and Chromium Concentra- tions in Bond Coatings on the Performance of Zirconia-Yttria Thermal Barriers,Thin Solid Films, Vol 73, 1980, p 481 -489
S. Stecura, Two-Layer Thermal Barrier Coatings, Part I: Effects of Composition and Temperature on Oxidation Behavior and Failure,Thin Solid Films, Vol 182, 1989, p 121–139
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Yoshiba, M., Abe, K., Aranami, T. et al. High-temperature oxidation and hot corrosion behavior of two kinds of thermal barrier coating systems for advanced gas turbines. JTST 5, 259–268 (1996). https://doi.org/10.1007/BF02645876
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DOI: https://doi.org/10.1007/BF02645876