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High-energy X-ray phase analysis of CMAS-infiltrated 7YSZ thermal barrier coatings: Effect of time and temperature

Published online by Cambridge University Press:  28 August 2020

Zachary Stein
Affiliation:
Department of Mechanical & Aerospace Engineering, University of Central Florida, Orlando, Florida32816, USA
Peter Kenesei
Affiliation:
Advanced Photon Source, Argonne National Laboratory, Lemont, Illinois60439, USA
Jun-Sang Park
Affiliation:
Advanced Photon Source, Argonne National Laboratory, Lemont, Illinois60439, USA
Jonathan Almer
Affiliation:
Advanced Photon Source, Argonne National Laboratory, Lemont, Illinois60439, USA
Ravisankar Naraparaju
Affiliation:
Institute of Materials Research, German Aerospace Centre (DLR), Cologne51170, Germany
Uwe Schulz
Affiliation:
Institute of Materials Research, German Aerospace Centre (DLR), Cologne51170, Germany
Seetha Raghavan*
Affiliation:
Department of Mechanical & Aerospace Engineering, University of Central Florida, Orlando, Florida32816, USA
*
a)Address all correspondence to this author. e-mail: seetha.raghavan@ucf.edu
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Abstract

Calcium–magnesium–alumino-silicate (CMAS) particulates enter the aero-engine in a sandy environment, melt and infiltrate into 7 wt% yttria-stabilized zirconia (7YSZ) thermal barrier coatings (TBCs), reducing their lifetime. This leads to chemical degradation in 7YSZ accompanied by tetragonal to monoclinic phase transformation upon cooling. In this work, electron-beam physical vapor deposition coatings were infiltrated with a synthetic CMAS. Synchrotron X-ray diffraction measurements show that CMAS infiltration at 1250 °C has about 43% higher monoclinic phase volume fraction (PVF) at the coating surface compared to 1225 °C and remains consistently higher throughout the coating depth. Additionally, the increase in annealing time from 1 to 10 h results in a 31% higher monoclinic phase at the surface. Scanning electron microscopy revealed the presence of globular monoclinic phases corresponding spatially with the above findings. These results resolve the impact of time and temperature on CMAS infiltration kinetics which is important for mitigation.

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Article
Copyright
Copyright © The Author(s), 2020, published on behalf of Materials Research Society by Cambridge University Press

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References

Miller, R.A.: Thermal barrier coatings for aircraft engines: History and directions. J. Therm. Spray Tech. 6, 35 (1997).CrossRefGoogle Scholar
Knipe, K., Manero, A.C., Siddiqui, S.F., Meid, C., Wischek, J., Okasinski, J., Almer, J., Karlsson, A.M., Bartsch, M., and Raghavan, S.: Inside the engine environment–synchrotrons reveal secrets of high-temperature ceramic coatings. Am. Ceram. Soc. Bull. 94, 22 (2015).Google Scholar
Sohn, Y., Kim, J., Jordan, E., and Gell, M.: Thermal cycling of EB-PVD/MCrAlY thermal barrier coatings: I. microstructural development and spallation mechanisms. Surf. Coat. Technol. 146, 7078 (2001).CrossRefGoogle Scholar
Schulz, U., Saruhan, B., Fritscher, K., and Leyens, C.: Review on advanced EB-PVD ceramic topcoats for TBC applications. Int. J. Appl. Ceram. Technol. 1, 302315 (2004).CrossRefGoogle Scholar
Naraparaju, R., Hüttermann, M., Schulz, U., and Mechnich, P.: Tailoring the EB-PVD columnar microstructure to mitigate the infiltration of CMAS in 7YSZ thermal barrier coatings. J. Eur. Ceram. Soc. 37, 261270 (2017).CrossRefGoogle Scholar
Krämer, S., Yang, J., Levi, C., and Johnson, C.: Thermochemical interaction of thermal barrier coatings with molten CaO-MgO-Al2O3-SiO2 (CMAS) deposits. J. Am. Ceram. Soc. 89, 31673175 (2006).CrossRefGoogle Scholar
Garces, H.F., Senturk, B.S., and Padture, N.P.: In situ Raman spectroscopy studies of high-temperature degradation of thermal barrier coatings by molten silicate deposits. Scr. Mater. 76, 2932 (2013).CrossRefGoogle Scholar
Viazzi, C., Bonino, J.P., Ansart, F., and Barnabé, A.: Structural study of metastable tetragonal YSZ powders produced via a sol–gel route. J. Alloys Compd. 452, 377383 (2006).CrossRefGoogle Scholar
Schulz, U.: Phase transformation in EB-PVD yttria partially stabilized zirconia thermal barrier coatings during annealing. J. Am. Ceram. Soc. 83, 904910 (2000).CrossRefGoogle Scholar
Naraparaju, R., Schulz, U., Mechnich, P., Döbber, P., and Seidel, F.: Degradation study of 7 wt.% yttria stabilised zirconia (7YSZ) thermal barrier coatings on aero-engine combustion chamber parts due to infiltration by different CaO–MgO–Al2O3–SiO2 variants. Surf. Coat. Technol. 260, 7381 (2014).CrossRefGoogle Scholar
Wu, J., Guo, H.B., Gao, Y.Z., and Gong, S.K.: Microstructure and thermo-physical properties of yttria stabilized zirconia coatings with CMAS deposits. J. Eur. Ceram. Soc. 31, 18811888 (2011).CrossRefGoogle Scholar
Borom, M.P., Johnson, C.A., and Peluso, L.A.: Role of environment deposits and operating surface temperature in spallation of air plasma sprayed thermal barrier coatings. Surf. Coat. Technol. 86, 116126 (1996).CrossRefGoogle Scholar
Bansal, N.P. and Choi, S.R.: Properties of CMAS glass from desert sand. Ceram. Int. 41, 39013909 (2015).CrossRefGoogle Scholar
Knipe, K.: In-situ synchrotron studies of turbine blade thermal barrier coatings under extreme environments. Electronic theses and dissertations, UCF STARS, 2014.Google Scholar
Knipe, K., Manero, A.C., Sofronsky, S., Okasinski, J., Almer, J., Wischek, J., Meid, C., Karlsson, A.M., Bartsch, M., and Raghavan, S.: Synchrotron X-ray diffraction measurements mapping internal strains of thermal barrier coatings during thermal gradient mechanical fatigue loading. J. Eng. Gas Turbines Power 137, 082506 (2015).CrossRefGoogle Scholar
Knipe, K., Manero, A.C., Siddiqui, S.F., Meid, C., Wischek, J., Okasinski, J., Almer, J., Karlsson, A.M., Bartsch, M., and Raghavan, S.: Strain response of thermal barrier coatings captured under extreme engine environments through synchrotron X-ray diffraction. Nat. Commun. 5, 4559 (2014).CrossRefGoogle ScholarPubMed
Bohorquez, E., Sarley, B., Hernandez, J., Hoover, R., Tetard, L., Naraparaju, R., Schulz, U., and Raghavan, S.: Investigation of the effects of CMAS-infiltration in EB-PVD 7% yttria-stabilized zirconia via Raman spectroscopy. In AIAA/ASCE/AHS/ASC Struct. Dyn. Mat. Conf., 96, Kissimmee, Florida, 8–12 January (2018).Google Scholar
Garvie, R.C. and Nicholson, P.S.: Phase analysis in zirconia systems. J. Am. Ceram. Soc. 55, 303305 (1972).CrossRefGoogle Scholar
Naraparaju, R., Mechnich, P., Schulz, U., and Mondragon Rodriguez, G.C.: The accelerating effect of CaSO4 within CMAS (CaO–MgO–Al2O3–SiO2) and its effect on the infiltration behavior in EB-PVD 7YSZ. J. Am. Ceram. Soc. 99, 13981403 (2016).CrossRefGoogle Scholar
Zhao, X., Wang, X., and Xiao, P.: Sintering and failure behaviour of EB-PVD thermal barrier coating after isothermal treatment. Surf. Coat. Technol. 200, 59465955 (2006).CrossRefGoogle Scholar
Wolfe, D.E., Singh, J., Miller, R.A., Eldridge, J.I., and Zhu, D.M.: Tailored microstructure of EB-PVD 8YSZ thermal barrier coatings with low thermal conductivity and high thermal reflectivity for turbine applications. Surf. Coat. Technol. 190, 132149 (2005).CrossRefGoogle Scholar
Barrett, C., Stein, Z., Hernandez, J., Naraparaju, R., Schulz, U., Tetard, L., and Raghavan, S.: Detrimental effects of sand ingression in jet engine ceramic coatings captured with Raman-based 3D rendering. (Publication In Review) 2020.Google Scholar
Naraparaju, R., Schulz, U., Raghavan, S., and Bohorquez, E.: Non-destructive CMAS-infiltration characterization of thermal barrier coatings. US Patent Pub. No. US20190293567A1. Granted 09/26/2019.Google Scholar