To investigate the impact of the high temperature water vapor environment on the corrosion behavior of MCrAlY/8YSZ thermal barrier coatings (TBCs), high-velocity oxy-fuel (HVOF) spray and atmospheric plasma spray (APS) are employed to prepare metal bond coatings with different structures and compositions on MM247 substrates. Subsequently, 8YSZ ceramic coatings are deposited onto each bond coating via APS to fabricate TBC systems with varying metal bond coating characteristics. The TBCs with different bond coating structures/compositions are subject to high-temperature water vapor corrosion tests at 1050 ℃ with water vapor contents of 0vol.%, 45vol.%, and 80vol.%, respectively. The corrosion behaviors of TBCs under these different conditions are compared, and the microstructure and composition of the corrosion products are analyzed for each system using SEM equipped with an EDS. The results indicate that after exposure to the water vapor corrosion tests at 1 050 ℃ with varying water vapor contents, the dual-layer oxide scale composed of spinel oxide and Al2O3 is observed on each TBC sample. The continuous and dense microstructure of the Al2O3 layer results in a slower growth rate. This continuous and dense structure effectively slows the outward diffusion of metal ions within the bond coating, thereby inhibiting the growth of the TGO layer. In contrast, the spinel oxide exhibits inconsistent growth with internal porosity. Its greater brittleness and accelerated growth rate readily induce crack initiation within the TGO layer, leading to premature failure of the thermal barrier coating system. Therefore, controlling the content of spinel oxide within the TGO layer is critical for extending the service life of thermal barrier coatings. In high temperature water vapor environments, spinel oxide formation is accelerated, thereby hastening the corrosion of the bond coating. An increase in water vapor content further promotes this process. A dense bond coating structure can effectively slow the outward diffusion of metal ions during high temperature water vapor corrosion, reducing the proportion of spinel oxide in the corrosion products and thus improving the water vapor corrosion resistance of the TBCs. In contrast, bond coatings prepared by atmospheric plasma spray inherently contain a certain level of porosity. These pores not only provide pathways for corrosive media to penetrate the bond coating, but also act as low-activation-energy diffusion paths for metal ions when they migrate outward to form corrosion products upon contact with the corrosive environment. Consequently, the pores serve as rapid diffusion channels for the outward diffusion of metal ions, ultimately accelerating the formation of corrosion products. In contrast, a single-layer bond coating produced by HVOF spray enables molten metal particles to impact the substrate with higher kinetic energy, resulting in a denser microstructure and a reduced formation rate of corrosion products. Furthermore, the incorporation of Ta into the bond coating further reduces the outward diffusion rate of metal ions, consequently inhibiting the growth rate of the spinel oxide under high temperature water vapor conditions. The Ta element segregates at elevated temperature, accumulating preferentially at grain boundaries and phase boundaries. These sites act as critical channels for the outward diffusion of metal ions during oxide scale growth. When Ta becomes enriched at these boundaries, the outward diffusion of metal ions is suppressed. As a result, the growth of the oxide layer becomes dominated by the inward diffusion of oxygen ions. However, the inward diffusion rate of oxygen ions is lower than the outward diffusion rate of metal ions, leading to an overall reduction in the oxide layer growth rate.
Key words
thermal barrier coating /
HVOF /
APS /
water vapor corrosion /
hydrogen gas turbine
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References
[1] DONG T S, KONG L C, FU B G, et al.Effect of CeO2 Doping on High Temperature Oxidation Resistance of YSZ TBCS[J]. Ceramics International, 2022, 48(24): 36450-36459.
[2] LEI X G, WANG Y F, WANG Q S, et al.A Case Study on CMAS Corrosion of an In-Situ Microstructure Modification YSZ TBCS Fabricated by EB-PVD[J]. Surface and Coatings Technology, 2021, 425: 127738.
[3] LAU H.Influence of Yttria on the Cyclic Lifetime of YSZ TBC Deposited on EB-PVD NiCoCrAlY Bondcoats and Its Contribution to a Modified TBC Adhesion Mechanism[J]. Surface and Coatings Technology, 2013, 235: 121-126.
[4] LAVASANI H Q, VALEFI Z, EHSANI N, et al.Studying the Effect of Spraying Parameters on the Sintering of YSZ TBC Using APS Method[J]. Surface and Coatings Technology, 2019, 360: 238-246.
[5] HE J H.Advanced MCrAlY Alloys with Doubled TBC Lifetime[J]. Surface and Coatings Technology, 2022, 448: 128931.
[6] NOWAK W, NAUMENKO D, MOR G, et al.Effect of Processing Parameters on MCrAlY Bondcoat Roughness and Lifetime of APS-TBC Systems[J]. Surface and Coatings Technology, 2014, 260: 82-89.
[7] DOLEKER K M, OZGURLUK Y, KARAOGLANLI A C.TGO Growth and Kinetic Study of Single and Double Layered TBC Systems[J]. Surface and Coatings Technology, 2021, 415: 127135.
[8] KALUSH A, TEXIER D, ECOCHARD M, et al.Size Effects on High Temperature Oxidation of MCrAlY Coatings Processed via APS and HVOF Depositions[J]. Surface and Coatings Technology, 2022, 440: 128483.
[9] CHEN Y, ZHAO X F, XIAO P.Effect of Surface Curvature on Oxidation of a MCrAlY Coating[J]. Corrosion Science, 2020, 163: 108256.
[10] 李丛, 赵雷, 徐连勇, 等. 掺氢/纯氢环境下燃气轮机的氢致损伤研究进展[J]. 材料导报, 2025, 39(9): 122-131.
LI C, ZHAO L, XU L Y, et al.Research Advances in Hydrogen Induced Damage of Gas Turbines in Hydrogen- Containing/Pure-Hydrogen Circumstances[J]. Materials Reports, 2025, 39(9): 122-131.
[11] 梅浩, 尚勇, 常可可, 等. 混氢燃气轮机用高温结构材料与热障涂层研究进展[J]. 航空材料学报, 2024, 44(5): 86-104.
MEI H, SHANG Y, CHANG K K, et al.Research Progress on High Temperature Structural Materials and Thermal Barrier Coatings for Hydrogen Mixing Gas Turbines[J]. Journal of Aeronautical Materials, 2024, 44(5): 86-104.
[12] HAYNES J A, UNOCIC K A, PINT B A.Effect of Water Vapor on the 1100 ℃ Oxidation Behavior of Plasma- Sprayed TBCS with HVOF NiCoCrAlX Bond Coatings[J]. Surface and Coatings Technology, 2013, 215: 39-45.
[13] LEYENS C, FRITSCHER K, GEHRLING R, et al.Oxide Scale Formation on an MCrAlY Coating in Various H2-H2O Atmospheres[J]. Surface and Coatings Technology, 1996, 82(1/2): 133-144.
[14] CHENG Y H, LI C, YUAN X H, et al.The Role of High-Temperature Water Vapor on Oxidation Behavior for CoNiCrAlHf Alloys at 1100 ℃[J]. Materials Characterization, 2024, 210: 113829.
[15] 杜仲. 界面氧化对等离子喷涂热障涂层失效行为的影响研究[D]. 北京: 北京理工大学, 2015.
DU Z.Study on the Influence of Interfacial Oxidation to Failure Behavior of Plasma Sprayed Thermal Barrier Coatings[D]. Beijing: Beijing Institute of Technology, 2015.
[16] 张啸. 等离子喷涂AlCoCrFeNi粘结层的氧化机制与失效行为[D]. 沈阳: 沈阳工业大学, 2024.
ZHANG X.Oxidation Mechanism and Failure Behavior of Plasma Sprayed AlCoCrFeNi Bond Coatings[D]. Shenyang: Shenyang University of Technology, 2024.
[17] 刘雨薇, 李淳, 冯世钊, 等. 长寿命热障涂层失效机制、材料选择及结构设计研究进展[J]. 中国表面工程, 2024, 37(5): 220-237.
LIU Y W, LI C, FENG S Z, et al.Research Progress on Failure Mechanism, Material Selection and Structural Design of Long-Life Thermal Barrier Coatings[J]. China Surface Engineering, 2024, 37(5): 220-237.
[18] FAN J B, WANG Q S, NING X J, et al.Microstructural Evolution and Failure Mechanisms of Thermal Barrier Coatings under Extreme Environmental Conditions[J]. Journal of the European Ceramic Society, 2025, 45(5): 117089.
[19] YANG H Z, ZOU J P, SHI Q, et al.Growth Stress and Interdiffusion Analysis of NiCoCrAlYTa Coating during Oxidation[J]. Surface Engineering, 2021, 37(6): 808-817.
[20] HAO E K, AN Y L, ZHAO X Q, et al.NiCoCrAlYTa Coatings on Nickel-Base Superalloy Substrate: Deposition by High Velocity Oxy-Fuel Spraying as Well as Investigation of Mechanical Properties and Wear Resistance in Relation to Heat-Treatment Duration[J]. Applied Surface Science, 2018, 462: 194-206.
[21] ZHANG X, ZHANG N N, XING B W, et al.Oxidation Behavior of AlCoCrFeNiSix High Entropy Alloy Bond Coatings Prepared by Atmospheric Plasma Spray[J]. Surface and Coatings Technology, 2023, 462: 129489.
[22] ZHANG H F, ZHANG X, ZHANG J, et al.Vacuum Plasma Sprayed AlCoCrFeNi High-Entropy Alloy Bond Coating: Vacuum Heat-Treatment, Microstructure Evolution and Oxidation Behavior Analysis[J]. Intermetallics, 2025, 184: 108836.
[23] ZHANG X, ZHANG N N, LIU M, et al.The Failure Behavior of Thermally Grown Oxide of the AlCoCrFeNi Bond Coating Prepared by Atmospheric Plasma Spray at 900-1 000 ℃[J]. Journal of Materials Research and Technology, 2023, 26: 6807-6822.
[24] LV X K, LI D S, DUAN W H, et al.Comprehensive Study of the Effect of Hf and Ta Co-Doped MCrAlY Bond Coat on the High-Temperature Properties of Thermal Barrier Coating[J]. Surfaces and Interfaces, 2024, 54: 105277.
[25] DUAN W H, HUANG B X, LI Y L, et al.Hf and Ta Co-Doping MCrAlY Alloy to Improve the Lifetime of Coatings[J]. Surface and Coatings Technology, 2023, 468: 129781.
Funding
National Key Research and Development Program of China (2024YFB3715200); Liaoning Province Science and Technology Major Project (2024JH1/11700039); Central-guided Local Scientific and Technological Development Joint Funds in Liaoning Province (IC24ZXK300); Research and Verification Project Key Technology for Advanced Heavy-duty Gas Turbines (J920)
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