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An analytical model for simulation of heat flow in plasma-sprayed thermal barrier coatings

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Abstract

Numerical (finite difference) and analytical models have been developed for the simulation of heat flow through plasma-sprayed coatings, allowing the effective thermal conductivity to be predicted as a function of microstructural parameters. The structure is assumed to be composed of lamellar material (splats), separated by (thin) pores, within which there are areas of contact (bridges). The analytical model is based on dividing the material into two regimes, within which the heat flow occurs either by unidirectional serial flow through lamellae and pores or by being funneled through the regions of the lamellae above and below the bridges. The validity of this model is demonstrated by a comparison of the predictions obtained from it and those obtained from the numerical model. The effects of pore geometry on conductive and radiative heat transfer within the coating have been investigated over a range of temperatures and gas pressures. It is shown that the main factor controlling the conductivity is the intersplat bridge area. Comparisons are also presented with experimental conductivity data, for cases in which some attempt has been made to characterize the key microstructural features. The study is oriented toward thermal barrier coatings, based on zirconiayttria top coats. It is noted that the effect of microstructural sintering, which tends to occur in these coatings under service conditions, can be predicted using this model.

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References

  1. R.A. Miller, Thermal Barrier Coatings for Aircraft Engines: History and Directions, J. Thermal Spray Technol., Vol 6, 1997, p 35–42

    CAS  Google Scholar 

  2. W. Beele, G. Marijnissen, and A. van Lieshout, The Evolution of Thermal Barrier Coatings: Status and Upcoming Solutions for Today’s Key Issues, Surf. Coat. Technol., Vol 121, 1999, p 61–67

    Article  Google Scholar 

  3. R. Hamacha, P. Fauchais, and F. Nardou, Influence of Dopant on the Thermal Properties of Two Plasma-sprayed Zirconia Coatings: 1. Relationship Between Powder Characteristics and Coating Properties, J Thermal Spray Technol., Vol 5, 1996, p 431–438

    CAS  Google Scholar 

  4. J.R. Nicholls, K.J. Lawson, A. Johnstone, and D.S. Rickerby, Low Thermal Conductivity EB-PVD Thermal Barrier Coatings, Mater. Sci. Forum, Vol 369–372, 2001, p 595–606

    Google Scholar 

  5. S. Gu, T.J. Lu, D.D. Hass, and H.N.G. Wadley, Thermal Conductivity of Zirconia Coatings with Zig-Zag Pore Microstructures, Acta Mater., Vol 49, 2001, p 2539–2547

    Article  CAS  Google Scholar 

  6. T.J. Lu, C.G. Levi, H.N.G. Wadley, and A.G. Evans, Distributed Porosity as a Control Parameter for Oxide Thermal Barriers Made by Physical Vapor Deposition, J. Am. Ceram. Soc., Vol 84, 2001, p 2937–2946

    CAS  Google Scholar 

  7. K.W. Schlichting, N.P. Padture, and P.G. Klemens, Thermal Conductivity of Dense and Porous Yttria-Stabilized Zirconia, J. Mater. Sci., Vol 36, 2001, p 3003–3010

    Article  CAS  Google Scholar 

  8. J.R. Nicholls, K.J. Lawson, A. Johnstone, and D.S. Rickerby, Methods to Reduce the Thermal Conductivity of EB-PVD TBCs, Surf. Coat. Technol., Vol 151, 2002, p 383–391

    Article  Google Scholar 

  9. S. Orain, Y. Scudeller, and T. Brousse, Structural and Microstructural Effects on the Thermal Conductivity of Zirconia Thin Films, Microscale Thermophys. Eng., Vol 5, 2001, p 267–275

    Article  CAS  Google Scholar 

  10. I. Sevostianov and M. Kachanov, Anisotropic Thermal Conductivities of Plasma-Sprayed Thermal Barrier Coatings in Relation to the Microstructure, J. Thermal Spray Technol., Vol 9, 2000, p 478–482

    Article  CAS  Google Scholar 

  11. P.A. Langhahr, R. Oberacker, and M.J. Hoffmann, Long-Term Behaviour and Application Limits of Plasma-Sprayed Zirconia Thermal Barrier Coatings, J. Am. Ceram. Soc., Vol 84, 2001, p 1301–1208

    Article  Google Scholar 

  12. D.M. Zhu and R.A. Miller, Thermal Conductivity and Elastic Modulus Evolution of Thermal Barrier Coatings under High Heat Flux Conditions, J. Thermal Spray Technol., Vol 9, 2000, p 175–180

    Article  CAS  Google Scholar 

  13. R. Dutton, R. Wheeler, K.S. Ravichandran, and K. An, Effect of Heat Treatment on the Thermal Conductivity of Plasma-Sprayed Thermal Barrier Coatings, J. Thermal Spray Technol., Vol 9, 2000, p 204–209

    Article  CAS  Google Scholar 

  14. D. Basu, C. Funke, and R.W. Steinbrech, Effect of Heat Treatment on Elastic Properties of Separated Thermal Barrier Coatings, J. Mater. Res., Vol 14, 1999, p 4643–4650

    CAS  Google Scholar 

  15. J.A. Thompson and T.W. Clyne, The Effect of Heat Treatment on the Stiffness of Zirconia Top Coats in Plasma-Sprayed TBCs, Acta Mater., Vol 49, 2001, p 1565–1575

    Article  CAS  Google Scholar 

  16. T.W. Clyne and P.J. Withers, An Introduction to Metal Matrix Composites, Cambridge University Press, Cambridge, UK, 1993

    Google Scholar 

  17. B. Shafiro and M. Kachanov, Anisotropic Effective Conductivity of Materials with Nonrandomly Oriented Inclusions of Diverse Ellipsoidal Shapes, J. Appl. Phys., Vol 87, 2000, p 8561–8569

    Article  ADS  CAS  Google Scholar 

  18. F. Cernuschi, P. Bianchi, M. Leoni, and P. Scardi, Thermal Diffusivity/Microstructure Relationship in Y-PSZ Thermal Barrier Coatings, J. Thermal Spray Technol., Vol 8, 1999, p 102–109

    Article  CAS  Google Scholar 

  19. R. McPherson, A Model for the Thermal Conductivity of Plasma-Sprayed Ceramic Coatings, Thin Solid Films, Vol 112, 1984, p 89–95

    Article  CAS  Google Scholar 

  20. C.J. Li and A. Ohmori, Relationships Between the Microstructure and Properties of Thermally Sprayed Deposits, J. Thermal Spray Technol., Vol 11, 2002, p 365–374

    Article  CAS  Google Scholar 

  21. S. Boirelavigne, C. Moreau, and R.G. Saintjacques, The Relationship Between the Microstructure and Thermal-Diffusivity of Plasma-Sprayed Tungsten Coatings, J. Thermal Spray Technol., Vol 4, 1995, p 261–267

    CAS  Google Scholar 

  22. T.J. Lu and J.W. Hutchinson, Thermal-Conductivity and Expansion of Cross-Ply Composites with Matrix Cracks, J. Mech. Phys. Solids, Vol 43, 1995, p 1175–1198

    Article  MATH  Google Scholar 

  23. D.Y. Tzou, The Effect of Internal Heat-Transfer in Cavities on the Overall Thermal-Conductivity, Int. J. Heat Mass Transfer, Vol 34, 1991, p 1839–1846

    Article  Google Scholar 

  24. Z. Hashin, The Differential Scheme and Its Application to Cracked Materials, J. Mech. Phys. Solids, Vol 36, 1988, p 719–734

    Article  MATH  MathSciNet  Google Scholar 

  25. T.H. Bauer, A General Analytical Approach Toward the Thermal-Conductivity of Porous-Media, Int. J. Heat Mass Transfer, Vol 36, 1993, p 4181–4191

    Article  MATH  CAS  Google Scholar 

  26. S. Raghavan, H. Wang, R.B. Dinwiddie, W.D. Porter, and M.J. Mayo, The Effect of Grain Size, Porosity and Yttria Content on the Thermal Conductivity of Nanocrystalline Zirconia, Scripta Mater., Vol 39, 1998, p 1119–1125

    Article  CAS  Google Scholar 

  27. K.S. Ravichandran, K. An, R.E. Dutton, and S.L. Semiatin, Thermal Conductivity of Plasma-Sprayed Monolithic and Multilayer Coatings of Alumina and Yttria-Stabilized Zirconia, J. Am. Ceram. Soc., Vol 83, 1999, p 673–682

    Google Scholar 

  28. T.J. Lu, C.G. Levi, H.N.G. Wadley, and A.G. Evans, Distributed Porosity as a Control Parameter for Oxide Thermal Barriers made by Physical Vapor Deposition, J. Am. Ceram. Soc., Vol 84, 2001, p 2937–2946

    Article  CAS  Google Scholar 

  29. F.P. Incropera and D.P. Dewitt, Introduction to Heat Transfer, John Wiley & Sons, 1996

  30. A.C. Fox and T.W. Clyne, The Gas Permeability of Plasma Sprayed Ceramic Coatings, Thermal Spray: A United Forum for Scientific and Technological Advances, C.C. Berndt, Ed., Sept. 15–18, 1997 (Indianapolis, IN), ASM International, 1998, p 483–490

  31. D.W. Lee and W.D. Kingery, Radiation Energy Transfer and Thermal Conductivity of Ceramic Oxides, J. Am. Ceram. Soc., Vol 43, 1960, p 594–605

    Article  CAS  Google Scholar 

  32. J.G. Peelen and R. Metselaar, Light Scattering by Pores in Polycrystalline Materials: Transmission Properties of Alumina, J. Appl. Phys., Vol 45, 1974, p 216–220

    Article  ADS  CAS  Google Scholar 

  33. J. Manara, R. Caps, F. Raether, and J. Fricke, Characterization of the Pore Structure of Alumina Ceramics by Diffuse Radiation Propagation in the Near Infrared, Opt. Commun., Vol 168, 1999, p 237–250

    Article  ADS  CAS  Google Scholar 

  34. R. Siegel and J.R. Howell, Thermal Radiation Heat Transfer, McGraw-Hill, New York, 1972

    Google Scholar 

  35. T. Makino, T. Kunitomo, I. Sakai, and H. Kinoshita, Thermal Radiation Properties of Ceramic Materials, Heat Transfer. Jap. Res., Vol 13, 1984, p 33–50

    Google Scholar 

  36. F. Cabannes and D. Billard, Measurement of Infrared-Absorption of Some Oxides in Connection with the Radiative-Transfer in Porous and Fibrous Materials, Int. J. Thermophys., Vol 8, 1987, p 97–118

    Article  CAS  Google Scholar 

  37. R. Siegel, Transient Thermal Analysis of a Translucent Thermal Barrier Coating on a Metal Wall, J. Heat Transfer, Vol 121, 1999, p 478–481

    CAS  Google Scholar 

  38. D.R. Clarke, Materials Selection Guidelines for Low Thermal Conductivity Barrier Coatings, Surf. Coat. Technol., Vol 163–164, 2003, p 67–74

    Article  Google Scholar 

  39. A.S. Samarskii and P.N. Vabishevich, Computational Heat Transfer, Vol 1, Mathematical Modelling, Wiley, Chichester, UK, 1995

    Google Scholar 

  40. J.C. Tannehill, D.A. Anderson, and R.H. Pletcher, Computational Fluid Mechanics and Heat Transfer, Taylor & Francis, Washington, D.C., 1997

    Google Scholar 

  41. J. Ilavsky, A.J. Allen, G.G. Long, S. Krueger, C.C. Berndt, and H. Herman, Influence of Spray Angle on the Pore and Crack Microstructure of Plasma-Sprayed Deposits, J. Am. Ceram. Soc., Vol 80, 1997, p 733–742

    Article  CAS  Google Scholar 

  42. A.J. Allen, J. Ilavsky, G.G. Long, J.S. Wallace, C.C. Berndt, and H. Herman, Microstructural Characterization of Yttria-Stabilized Zirconia Plasma-Sprayed Deposits Using Multiple Small-Angle Neutron Scattering, Acta Mater., Vol 49, 2001, p 1661–1675

    Article  CAS  Google Scholar 

  43. A. Kulkarni, Z. Wang, T. Nakamura, S. Sampath, A. Goland, H. Herman, J. Allen, J. Ilavsky, G. Long, J. Frahm, and R.W. Steinbrech, Comprehensive Microstructural Characterization and Predictive Property Modeling of Plasma-Sprayed Zirconia Coatings, Acta Mater., Vol 51, 2003, p 2457–2475

    Article  CAS  Google Scholar 

  44. H. Boukari, A.J. Allen, G.G. Long, J. Ilavsky, J.S. Wallace, C.C. Berndt, and H. Herman, Small-Angle Neutron Scattering Study of the Role of Feedstock Particle Size on the Microstructural Behavior of Plasma-Sprayed Yttria-Stabilized Zirconia Deposits, J. Mater. Res., Vol 18, 2003, p 624–634

    CAS  Google Scholar 

  45. G. Trapaga, E.F. Matthys, J.J. Valencia, and J. Szekely, Fluid Flow, Heat Transfer and Solidification of Molten Metal Droplets Impinging on Substrates; Comparison of Numerical and Experimental Results, Metall. Trans., Vol 23B, 1992, p 701–718

    CAS  Google Scholar 

  46. H. Zhang, Theoretical Analysis of Spreading and Solidification of Molten Droplet During Thermal Spray Deposition, Int. J. Heat Mass Transfer, Vol 42, 1999, p 2499–2508

    Article  MATH  CAS  Google Scholar 

  47. T. Bennett and D. Poulikakos, Splat-Quench Solidification: Estimating the Maximum Spreading of a Droplet Impacting a Solid Surface, J. Mater. Sci., Vol 28, 1993, p 963–970

    Article  Google Scholar 

  48. R. McPherson, A Review of Microstructure and Properties of Plasma Sprayed Ceramics Coatings, Surf. Coat. Technol., Vol 39/40, 1989, p 173–181

    Article  Google Scholar 

  49. D.M. Zhu and R.A. Miller, Sintering and Creep Behaviour of Plasma-Sprayed Zirconia- and Hafnia-Based Thermal Barrier Coatings, Surf. Coat. Technol., Vol 109, 1998, p 114–120

    Article  Google Scholar 

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Golosnoy, I.O., Tsipas, S.A. & Clyne, T.W. An analytical model for simulation of heat flow in plasma-sprayed thermal barrier coatings. J Therm Spray Tech 14, 205–214 (2005). https://doi.org/10.1361/10599630523764

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  • DOI: https://doi.org/10.1361/10599630523764

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