EBSD Analysis and Assessment of Porosity in Thermal Barrier Coatings Produced by Axial Suspension Plasma Spraying (ASPS)

Abstract:

Axial suspension plasma spraying (ASPS) is a relatively new, innovative spraying technique which has produced thermal barrier coatings (TBCs) with attractive properties such as high durability and low thermal conductivity. Using a suspension, it is possible to spray with finer powder particles resulting in coatings that have a columnar microstructure and contain a wide range of pore sizes, both nm-and μm-sized pores. To optimize the thermal properties and to maintain them during service of the components, it will be important to design TBCs with optimal porosity. Hence, an important part in the assessment of ASPS coatings is therefore the characterization of the microstructure and how it is build up, and the determination of porosity. Both aspects are addressed by performing measurement on splats and ASPS-coating using electron backscatter diffraction (EBSD) technique and by measuring porosity by Mercury Intrusion Porosimetry (MIP).

• Periodical: Materials Science Forum (Volume 879)
• Pages: 972-977
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.879.972
• Online since: November 2016
• Authors: Uta Klement*, Johanna Ekberg, Ashish Ganvir
• Keywords: Axial Suspension Plasma Spraying, Electron Backscatter Diffraction (EBSD), Mercury Intrusion Porosimetry, Porosity, Scanning Electron Microscopy (SEM), Thermal Barrier Coatings (TBCs), XRM

References

[1] I.O. Golosnoy, A. Cipitria, T.W. Clyne, Heat transfer through plasma-sprayed thermal barrier coatings in gas turbines: A review of recent work, J. Therm. Spray Technol. 18 (2009) 809-821.

DOI: 10.1007/s11666-009-9337-y

[2] U. Schulz, C. Leyens, K. Fritscher, M. Peters, B. Saruhan-Brings, O. Lavigne, J. M. Dorvaux, M. Poulain, R. Mévrel, and M. Caliez, Some recent trends in research and technology of advanced thermal barrier coatings, Aerosp. Sci. Technol. 7 (2003).

DOI: 10.1016/s1270-9638(02)00003-2

[3] Z. Tang, H. Kim, I. Yaroslavski, G. Masindo, Z. Celler, and D. Ellsworth, Novel thermal barrier coatings produced by axial suspension plasma spray, Proceedings of the Internat. Thermal Spray Conference, 27-29 Sep 2011, Hamburg, Germany, DVS Media, Düsseldorf, 571-575.

DOI: 10.31399/asm.cp.itsc2011p0571

[4] S. Kozerski, L. Łatka, L. Pawlowski, F. Cernuschi, F. Petit, C. Pierlot, H. Podlesak, J. P. Laval, Preliminary study on suspension plasma sprayed ZrO2+8wt. % Y2O3 coatings, J. Eur. Ceram. Soc. 31 (2011) 2089-(2098).

DOI: 10.1016/j.jeurceramsoc.2011.05.014

[5] N. Curry, K. VanEvery, T. Snyder, N. Markocsan, Thermal conductivity analysis and lifetime testing of suspension plasma-sprayed thermal barrier coatings, Coatings 4 (2014) 630-50.

DOI: 10.3390/coatings4030630

[6] Y. Zhao, D. Li, X. Zhong, H. Zhao, L. Wang, F. Shao, C. Liu, and S. Tao, Thermal shock behaviors of YSZ thick thermal barrier coatings fabricated by suspension and atmospheric plasma spraying, Surf. Coatings Technol. 249 (2014) 48-55.

DOI: 10.1016/j.surfcoat.2014.03.046

[7] A. Ganvir, N. Curry, S. Björklund, N. Markocsan, P. Nylén, Characterization of microstructure and thermal properties of YSZ coatings obtained by axial suspension plasma spraying (ASPS), J. Therm. Spray Technol. 24 (2015) 1195-1204.

DOI: 10.1007/s11666-015-0263-x

[8] K. VanEvery, M.J.M. Krane, R.W. Trice, H. Wang, W. Porter, M. Besser, D. Sordelet, J. Ilavsky, J. Almer, Column formation in suspension plasma-sprayed coatings and resultant thermal properties, J. Therm. Spray Technol. 20 (2011) 817–828.

DOI: 10.1007/s11666-011-9632-2

[9] P. Sokolowski, L. Pawlowski, D. Dietrich, T. Lampke, D. Jech, Advanced microscopic study of suspension plasma-sprayed zirconia coatings with different microstructures, J. Therm. Spray Technol. 25 (2016) 94-104.

DOI: 10.1007/s11666-015-0310-7

[10] A. Joulia, G. Bolelli, E. Gualtieri, L. Lusvarghi, S. Valeri, M. Vardelle, S. Rossignol, A. Vardelle, Comparing the deposition mechnisms in suspension plasma spray (SPS) and solution precursor plasma spray (SPPS) deposition of yttria-stabilized zirconia (YSZ), J. Eur. Ceram. Soc. 34 (2014).

DOI: 10.1016/j.jeurceramsoc.2014.05.024

[11] A. Ganvir, N. Curry, N. Markocsan, P. Nylén, M. Vilemova, Z. Pala, Influence of microstructure on thermal properties of columnar axial suspension plasma sprayed thermal barrier coatings, Proceedings of the International Thermal Spray Conference, May 11-14, 2015, Long Beach, California, USA, ASM International, 498-505.

DOI: 10.1007/s11666-015-0355-7

[12] A. Tkachuk, F. Duewer, H. Cui, M. Feser, S. Wang, W. Yun, X-ray computed tomography in Zernike phase contrast mode at 8 keV with 50-nm resolution using Cu rotating anode X-ray source, Z. Kristallogr. 222 (2007) 650-655.

DOI: 10.1524/zkri.2007.222.11.650

[13] Carl Zeiss X-ray Microscopy, Inc., X-ray Nanotomography in the Laboratory with ZEISS Xradia Ultra 3D X-ray Microscopes, White Paper. Pleasanton, CA, USA, 2015. Retrieved from http: /pages. microscopy. zeiss. com/X-ray-Nanotomography-in-the-Laboratory-with-ZEISS-Xradia-Ultra. html.

DOI: 10.58286/26644

[14] A.P. Merkle, J. Gelb, The Ascent of 3D X-ray Microscopy in the Laboratory, Microscopy Today (2013) 18-23.

DOI: 10.1017/s1551929513000060

[15] To be published.