There are many sets of information in the literature (e.g., papers, books and websites) about the great achievements that are expected for aerospace gas turbine engines by the employment of ceramic matrix composites (CMCs) and thermally sprayed environmental barrier coatings (EBCs) in their hot zones (e.g., combustion chambers, vanes, shrouds, blades and afterburners). Among these achievements, it is typically highlighted (i) turbine weight reduction, (ii) reduced fuel consumption, (iii) higher operation temperatures, (iv) superior thrust-to-weight ratio and (v) lower emission of toxic gases to the atmosphere. Although these achievements are true, they are generally not well-explained to the reader on how together they come to be. In addition, according to “conventional wisdom”, some of these engineering feats are in fact opposing each other (e.g., higher operation temperatures versus lower emissions). The objective of this tutorial paper is to present the reader how these feats are achieved by the concomitant combination of imaginative engineering. It will explain the non-stop driving force for increasing combustion temperatures; show the basic concepts of CMCs, the paramount need of EBCs, and the complexity of creating EBC architectures via air plasma spray (APS). Finally, highlights on how EBCs/CMCs are tested at high temperature will be provided. The content of this paper shall be understood by anyone with basic knowledge in materials processing and surface engineering.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
Tax calculation will be finalised during checkout.
I. Spitsberg and J. Steibel, Thermal and Environmental Barrier Coatings for SiC/SiC CMCs in Aircraft Engine Application, Int. J. Appl. Ceram. Technol., 2004, 1(4), p 291–301.
N.P. Padture, Advanced Structural Ceramics in Aerospace Propulsion, Nat. Mater., 2016, 15, p 804–809.
A.G. Evans and D.B. Marshall, The Mechanical Behavior of Ceramic Matrix Composites, Acta Metall., 1989, 37(10), p 2567–2583.
J.A. Dever, M.V. Nathal and J.A. DiCarlo, Research on High-Temperature Aerospace Materials at NASA Glenn Research Center, J. Aerosp. Eng., 2013, 26(2), p 500–514.
E.J. Opila, J.L. Smialek, R.C. Robinson, D.S. Fox and N.S. Jacobson, SiC Recession Caused by SiO2 Scale Volatility under Combustion Conditions: II, Thermodynamics and Gaseous-diffusion Model, J. Am. Ceram. Soc., 1999, 82(7), p 1826–1834.
W. Braue and P. Mechnich, Tailoring Protective Coatings for All-oxide Ceramic Matrix Composites in High Temperature/High Heat Flux Environments and Corrosive Media, Mater. Sci. Eng. Technol. (Materialwissenschaft und Werkstofftechnik), 2007, 38(9), p 690–697.
K.N. Lee, D.S. Fox, J.I. Eldridge, D. Zhu, R.C. Robinson, N.P. Bansal and R.A. Miller, Upper Temperature Limit of Environmental Barrier Coatings Based on Mullite and BSAS, J. Am. Ceram. Soc., 2003, 86(8), p 1299–1306.
Y. Xu, X. Hu, F. Xu and K. Li, Rare Earth Silicate Environmental Barrier Coatings: Present Status and Prospective, Ceram. Int., 2017, 43, p 5847–5855.
U. Steinhauser, W. Braue, J. Goring, B. Kanka and H. Schneider, A New Concept for Thermal Protection of All-mullite composites in Combustion Chambers, J. Eur. Ceram. Soc., 2000, 20, p 651–658.
P. Mechnich and W. Braue, Air Plasma-sprayed Y2O3 Coatings for Al2O3/Al2O3 Ceramic Matrix Composites, J. Eur. Ceram. Soc., 2013, 33, p 2645–2653.
D.R. Clarke, M. Oechsner and N.P. Padture, Thermal-Barrier Coatings for More Efficient Gas-Turbine Engines, MRS Bull., 2012, 37(10), p 891–898.
S. Farokhi, Aircraft Propulsion—2nd Edition, Wiley, Chichester, 2015, p 8–9
J.H. Perepezko, The Hotter the Engine the Better, Science, 2009, 326, p 1068–1069.
A.H. Lefebvre and D.R. Ballal, Gas Turbine Combustion—Alternative Fuels and Emissions, 3rd Edition Edition, CRC Press, Boca Raton, 2010, p 91–92
Rolls-Royce—The Jet Engine, Renault Printing Co Ltd, Birmingham, 1996, p 35–37
T. Bhatia, D. Jarmon, J. Shi, S. Kearney, A. Kojovic, J. Hu and A. Prociw, CMC Combustor Liner Demonstration in a Small Helicopter Engine, in Proceedings of ASME TurboExpo 2010: Power for Land, Sea and Air, paper #GT2010-23810, p 509–513. https://doi.org/10.1115/GT2010-23810
G. Leonard and J. Stegmaier, Development of an Aeroderivative Gas Turbine Dry Low Emissions Combustion System, J. Eng. Gas Turbines Power, 1994, 116, p 542–546.
https://www.gpo.gov/fdsys/pkg/FR-2012-06-18/pdf/2012-13828.pdf (February 16, 2018)
K.N. Lee, Yb2Si2O7 Environmental Barrier Coatings with Reduced Bond Coat Oxidation Rates Via Chemical Modifications for Long Life, J. Am. Ceram. Soc., 2019, 102(3), p 1507–1521.
K.N. Lee, Current Status of Environmental Barrier Coatings for Si-Based Ceramics, Surf. Coat. Technol., 2000, 133–134, p 1–7.
K.N. Lee, J.I. Eldridge and R.C. Robinson, Residual Stresses and Their Effects on the Durability of Environmental Barrier Coatings for SiC Ceramics, J. Am. Ceram. Soc., 2005, 88(12), p 3483–3488.
E.J. Opila and R. Hann, Paralinear Oxidation of CVD SiC in Water Vapor, J. Am. Ceram. Soc., 1997, 80(1), p 197–205.
K.N. Lee, Environmental barrier coatings for CMCs, Ceramic Matrix Composites. N.P. Bansal, J. Lamon Ed., Wiley, New York, 2015, p 430–451
K.N. Lee, D.S. Fox and N.P. Bansal, Rare Earth Silicate Environmental Barrier Coatings for SiC/SiC Composites and Si3N4 Ceramics, J. Eur. Ceram. Soc., 2005, 25, p 1705–1715.
N.S. Jacobson, Silica Activity Measurements in the Y2O3–SiO2 System and Applications to Modeling of Coating Volatility, J. Am. Ceram. Soc., 2014, 97, p 1959–1965.
G.C.C. Costa and N.S. Jacobson, Mass Spectrometric Measurements of the Silica Activity in the Yb2O3–SiO2 System and Implications to Assess the Degradation of Silicate-Based Coatings in Combustion Environments, J. Eur. Ceram. Soc., 2015, 35, p 4259–4267.
M. Fritsch, H. Klemm, The water vapor hot gas corrosion behavior of Al2O3-Y2O3 materials, Y2SiO5 and Y3Al5O12-coated alumina in a combustion environment, in The 30th Int. Conf. & Exp. On Adv. Ceram. & Composites. Cocoa Beach, FL; January 2006.
R.A. Golden, K. Mueller and E.J. Opila, Thermochemical Stability of Y2Si2O7 in High-Temperature Water Vapor, J. Am. Ceram. Soc., 2020, 103(8), p 4517–4535.
B.E. Deal and A.S. Grove, General Relationship for the Thermal Oxidation of Silicon, J. Appl. Phys., 1965, 36(12), p 3770–3778.
E.J. Opila, Variation of the Oxidation Rate of Silicon Carbide with Water-Vapor Pressure, J. Am. Ceram. Soc., 1999, 82(3), p 625–636.
B.T. Richards, K.A. Young, F. de Franqueville, S. Sehr, M.R. Begley and H.N.G. Wadley, Response of Ytterbium Disilicate-Silicon Environmental Barrier Coatings to Thermal Cycling in Water Vapor, Acta Mater., 2016, 106, p 1–14.
K.N. Lee and M. van Roode, Environmental Barrier Coatings Enhance Performance of SiC/SiC Ceramic Matrix Composites, Am. Ceram. Soc. Bulletin, 2019, 98(3), p 46–53.
K. Grant, S. Kramer, J. Lofvander and C. Levi, CMAS Degradation of Environmental Barrier Coatings, Surf. Coat. Technol., 2007, 202, p 653–657.
K. Grant, S. Kramer, G. Seward and C. Levi, Calcium-Magnesium-Silicate Interaction with Yttrium Monosilicate Environmental Barrier Coatings, J. Am. Ceram. Soc., 2010, 93(10), p 3504–3511.
J. Harder, J. Ramirez-Rico, J.D. Almer, K.N. Lee and K.T. Faber, Chemical and Mechanical Consequences of Environmental Barrier Coating Exposure to Calcium-Magnesium-Aluminosilicate, J. Am. Ceram. Soc., 2011, 94(S1), p S178–S185.
F. Stolzenburg, M.T. Johnson, K.N. Lee, N.S. Jacobson and K.T. Faber, The Interaction of Calcium-Magnesium-Aluminum-Silicate with Ytterbium Silicate Environmental Barrier Materials, Surf. Coat. Technol., 2015, 284, p 44–50.
N.P. Padture, Environmental Degradation of High-Temperature Protective Coatings for Ceramic-Matrix Composites in Gas-Turbine Engines. NPJ Mater. Degrad. 11 (2019).
K.N. Lee, H. Fritze and Y. Ogura, Progress in Ceramic Gas Turbine Development, Vol 2, M. van Roode, M. Ferber, D.W. Richerson Ed., ASME Press, New York, 2003, p 641–664
K.N. Lee, R.A. Miller and N.S. Jacobson, New generation of Plasma-Sprayed Mullite Coatings on Silicon-Carbide, J. Am. Ceram. Soc., 1995, 78(3), p 705–710.
G.S. Corman, Melt Infiltrated Ceramic Matrix Composites for Shrouds and Combustor Liners of Advanced Industrial Gas Turbines. Advanced Materials for Advance Industrial Gas Turbines (AMAIGT) Program Final Report. U.S. Department of Energy Cooperative Agreement DE-FC26-00CH11047, December 2010.
W.G. Mao, J.P. Jiang, Y.C. Zhou and C. Luc, Effects of Substrate Curvature Radius, Deposition Temperature and Coating Thickness on the Residual Stress Field of Cylindrical Thermal Barrier Coatings, Surf. Coat. Technol., 2011, 205, p 3093–3102.
C. Gatzen, D.E. Mack, O. Guillon and R. Vaßen, YAlO3-A Novel Environmental Barrier Coating for Al2O3/Al2O3–Ceramic Matrix Composites, Coatings, 2019, 9, p 609.
M. Fritsch, Heißgaskorrosion Keramischer Werkstffe in H2O-Haltigen RauchgasatmosphärenO-Haltigen Rauchgasatmosphären, Fraunhofer IRB Verlag, TU Dresden, Dresden, 2007.
M. Fritsch, H. Klemm, M. Herrmann, A. Michaelis and B. Schenk, The Water Vapour Hot Gas Corrosion of Ceramic Materials, Ceram. Forum Int., 2010, 87, p 11–12.
B.T. Richards, H. Zhao and H.N.G. Wadley, Structure, Composition, and Defect Control During Plasma Spray Deposition of Ytterbium Silicate Coatings, J. Mater. Sci., 2015, 50, p 7939–7957.
E. Garcia, H. Lee and S. Sampath, Phase and Microstructure Evolution in Plasma Sprayed Yb2Si2O7 Coatings, J. Eur. Ceram. Soc., 2019, 39, p 1477–1486.
E. Bakan, Y.J. Sohn, W. Kunz, H. Klemm and R. Vaßen, Effect of Processing on High-Velocity Water Vapor Recession Behavior of Yb-Silicate Environmental Barrier Coatings, J. Eur. Ceramic Soc., 2019, 39, p 1507–1513.
E. Bakan et al., Yb2Si2O7 Environmental Barrier Coatings Deposited by Various Thermal Spray Techniques: A Preliminary Comparative Study, J. Therm. Spray. Tech., 2017, 26, p. 1011–1024.
R. Vaßen, E. Bakan, C. Gatzen, S. Kim, D.E. Mack and O. Guillon, Environmental Barrier Coatings Made by Different Thermal Spray Technologies, Coatings, 2019, 9, p 784. https://doi.org/10.3390/coatings9120784
C. Gatzen, D.E. Mack, O. Guillon and R. Vaßen, Surface Roughening of Al2O3/Al2O3 Ceramic Matrix Composites by Nanosecond Laser Ablation Prior to Thermal Spraying, J. Laser Appl., 2019, 31, p 022018. https://doi.org/10.2351/1.5080546
C.M. Weyant and K.T. Faber, Processing–Microstructure Relationships for Plasma-Sprayed Yttrium Aluminum Garnet, Surf. Coat. Technol., 2008, 202, p 6081–6089.
R. S. Lima, APS Deposition of Y2O3 EBCs via the Metco 3MB APS Torch Using N2/H2 Plasma (NRC # 190322B1), unpublished research.
E. J. Opila, N. S. Jacobson, D. L. Myers and E. H. Copland, Predicting Oxide Stability in High Temperature Water Vapor, J. Metals, January (2006) 22-28.
M. Fritsch, H. Klemm, M. Herrmann and B. Schenk, Corrosion of Selected Ceramic Materials in Hot Gas Environment, J. Eur. Ceram. Soc., 2006, 26, p 3557–3565.
L. Lebel, R. Boukhili and S. Turenne, Damage to an A-N720 Ceramic Matrix Composite Under Simulated Gas Turbine Static Component Conditions Using Laser Heating, J. Compos. Mater., 2018, 52(30), p 4127–4138.
B. J. Harder, D. Zhu, M. P. Schmitt and D. E. Wolfe, High Temperature Multilayer Environmental Barrier Coatings Deposited Via Plasma Spray-Physical Vapor Deposition, https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150000326.pdf (June 1, 2020).
E. Bakan, G. Mauer, Y.H. Sohn, D. Koch and R. Vaßen, Application of High-Velocity Oxygen-Fuel (HVOF) Spraying to the Fabrication of Yb-Silicate Environmental Barrier Coatings, Coatings, 2017, 7, p 55. https://doi.org/10.3390/coatings7040055
E. Darthout, A. Quet, N. Brady and F. Gitzhofer, Lu2O3-SiO2-ZrO2 Coatings for Environmental Barrier Application by Solution Precursor Plasma Spraying and Influence of Precursor Chemistry, J. Therm. Spray Technol., 2014, 23(3), p 325–332.
C. Jiang, D. Cietek, R. Kumar and E.H. Jordan, Ytterbium Silicate Environmental Barrier Coatings Deposited Using the Solution-Based Precursor Plasma Spray, J. Thermal Spray Technol., 2020 https://doi.org/10.1007/s11666-020-01046-1
R.T. Bhatt, S.R. Choi, L.M. Cosgriff, D.S. Fox and K.N. Lee, Impact Resistance of Environmental Barrier Coated SiC/SiC Composites, Mater. Sci. Eng. A, 2008, 476, p 8–19.
Y. Okita, Y. Mizokami and J. Hasegawa, Experimental and Numerical Investigation of Environmental Barrier Coated Ceramic Matrix Composite Turbine Airfoil Erosion. J. Eng. Gas Turbines Power.
N.L. Ahlborg and D. Zhu, Calcium–Magnesium Aluminosilicate (CMAS) Reactions and Degradation Mechanisms of Advanced Environmental Barrier Coatings, Surf. Coat. Technol., 2013, 237, p 79–87.
H. Zhao, B.T. Richards, C.G. Levi and H.N.G. Wadley, Molten Silicate Reactions with Plasma Sprayed Ytterbium Silicate Coatings, Surf. Coat. Technol., 2016, 288, p 151–162.
F. Stolzenburg, P. Kenesei, J. Almer, K.N. Lee, M.T. Johnson and K.T. Faber, The Influence of Calcium-Magnesium-Aluminosilicate Deposits on Internal Stresses in Yb2Si2O7 Multilayer Environmental Barrier Coatings‘, Acta Mater., 2016, 105, p 189–198.
K.-I. Lee, L.T. Wu, R.T. Wub and P. Xiao, Mechanisms and Mitigation of Volcanic Ash Attack on Yttria Stablized Zirconia Thermal Barrier Coatings, Surf. Coat. Technol., 2014, 260, p 68–72.
D.L. Myers and N.S. Jacobson, Identification of Volatile Metal Hydroxides with Free Jet Expansion Sampling Mass Spectrometry, Calphad, 2019, 65, p 73–78.
T. Steinke, D. Sebold, D.E. Mack, R. Vaßen and D. Stöver, Novel Test Approach for Plasma-Sprayed Coatings Tested Simultaneously Under CMAS and Thermal Gradient Cycling Conditions, Surf. Coat. Technol., 2010, 205, p 2287–2295.
I. Yuri, T Hisamatsu, Recession rate prediction for ceramic materials in combustion gas flow, in Proceeding of SME Turbo Expo 2003 June 16–19, Atlanta, GA. CEPRI
J. Steibel, Ceramic Matrix Composites Taking Flight at GE Aviation, Am. Ceram. Soc. Bull., 2019, 98(3), p 30–33.
https://www.aero-mag.com/ge-aviation-ge9x-boeing-777x/ (February 3, 2020)
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
This article is an invited paper. The authors were invited based on their experience, knowledge, and expertise in this area to provide expert perspectives on a subject relevant to thermal spray. The views expressed in the paper are those of the author(s).
Dr Dongming Zhu passed away May 30, 2018.
About this article
Cite this article
Lee, K.N., Zhu, D. & Lima, R.S. Perspectives on Environmental Barrier Coatings (EBCs) Manufactured via Air Plasma Spray (APS) on Ceramic Matrix Composites (CMCs): A Tutorial Paper. J Therm Spray Tech (2021). https://doi.org/10.1007/s11666-021-01168-0
- air plasma spray (APS)
- ceramic matrix composites (CMCs)
- environmental barrier coatings (EBCs)
- gas turbine engines
- oxide-oxide CMC
- SiC/SiC CMC