Study on the Oxidation Behavior of LPPS MCrAlY Coatings at High Temperature: Part II Coating Microstructure Development

Abstract:

MCrAlY can be used as bond coats for thermal barrier coatings (TBCs) with good ductility and excellent resistance against high temperature oxidation and hot corrosion. The behavior of the microstructure development in the MCrAlY coatings plays a key role on the oxidation resistance. In this paper, the microstructure in the coatings oxidized at 750~1100 °C was analyzed. The formation of the phases and their fraction were studied by comparing thermodynamic simulation results with the experimental observations. At higher temperatures (>1000 °C) β-to-γ’-to-γ phase transformation took place while at lower temperatures (<1000 °C) β phase would transfer to γ directly. The results show that the simulation can semi-quantitatively predict the microstructure formed in the coating.

• Periodical: Materials Science Forum (Volume 1035)
• Pages: 584-590
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1035.584
• Online since: June 2021
• Authors: Kang Yuan*, Zhao Ran Zheng
• Keywords: Diffusion, MCrAlY, Microstructure, Oxidation

References

[1] W. Brandl, H.J. Grabke, D. Toma, and J. Krüger, The oxidation behaviour of sprayed MCrAY coatings, Surf. Coat. Techn., 1996, 86, pp.41-47.

DOI: 10.1016/s0257-8972(96)03039-3

[2] M.J. Pomeroy, Coatings for gas turbine materials and long term stability issues. Materials & Design, 2005. 26(3). 223-231.

DOI: 10.1016/j.matdes.2004.02.005

[3] W. Braue, K. Fritscher, et al., Nucleation and Growth of Oxide Constituents on NiCoCrAlY Bond Coats during the Different Stages of EB-PVD TBC Deposition and Upon Thermal Loading., Materials Science Forum 461-464, 899-906.

DOI: 10.4028/www.scientific.net/msf.461-464.899

[4] W. Brandl, H.J. Grabke, et al., The oxidation behaviour of sprayed MCrAly coatings., 86, 41-47 (1996).

DOI: 10.1016/s0257-8972(96)03039-3

[5] Y.H. Sohn, J.H. Kim, et al., Thermal cycling of EB-PVD/MCrAlY thermal barrier coatings: I. Microstructural development and spallation mechanisms., Surf. Coat. Tech. 146-147, 70-78.

DOI: 10.1016/s0257-8972(01)01478-5

[6] K.V. Dahl, J. Hald, A. Horsewell, Interdiffusion Between Ni-Based Superalloy and MCrAlY Coating., Defect & Diffusion Forum 258-260, 73-78 (2006).

DOI: 10.4028/www.scientific.net/ddf.258-260.73

[7] K.V. Dahl, J. Hald, Estimation of metal temperature of MCrAlY coated IN738 components based on inter-diffusion behaviour., Energy Materials 1, 106-115. [3] G.R. Mettam, L.B. Adams, How to prepare an electronic version of your article, in: B.S. Jones, R.Z. Smith (Eds.), Introduction to the Electronic Age, E-Publishing Inc., New York, 1999, pp.281-304.

DOI: 10.1179/174892306x99723