Analysis of residual stresses in bioinert inorganic plasma sprayed ceramic coatings

  • Mihailo R. Mrdak Research and Development Center IMTEL Communications a.d., Belgrade, Republic of Serbia
Keywords: Substrates, Stress, Coatings, Ceramics,

Abstract


One of the factors for a successful application of ceramic coatings on biomedical implants is the compatibility of the physical and mechanical properties of coatings with the metal substrates of implants. Temperature and temperature gradient in the coating during powder deposition play an important role in the final quality of the coating. The coefficients of thermal expansion and thermal conductivity of the coating and the substrate are different, which affects the growth of residual stresses in coatings. To reduce the difference between the physical characteristics of the coating and the substrate to a minimum, the coating surface temperature and the substrate surface temperature must be kept under control during the deposition of powder. It is therefore of particular importance to control residual stresses in ceramic coatings in order to secure service life of coatings and implants. The paper describes a model of plasma heat transfer and predicts the distribution of residual stresses in the deposited coatings; it also describes the radiography techniques for measuring residual stresses in ceramic coatings. The  aim of this paper is to describe the effect of powder deposition rates as well as the effect of the changes in the thickness and the thermal conductivity of the ZrO2CaO coating  on  the  level  and  the  sign  of residual stresses. The paper also presents the influence of the bonding coating, and the changes in the thickness of bonding and the ceramic ZrO2MgO coating as well as the heat treatment on the level and the sign of residual stresses. It was found that the increase of the total thickness of the coating increases the proportion of residual stresses on the surface and the edges of the coating.

 

Author Biography

Mihailo R. Mrdak, Research and Development Center IMTEL Communications a.d., Belgrade, Republic of Serbia
Doctor of Technical Sciences

References

Clyne, T.W. & Gill, S.C. 1996. Residual Stresses in Thermal Spray Coatings and Their Effect on Interfacial Adhesion. Journal of Thermal Spray Technology, 5, pp.401–418. Available at: https://doi.org/10.1007/BF02645271.

Greving, D.J., Rybicki, E.F. & Shadley, J.R. 1994. Through-Thickness Residual Stress Evaluations for Several Industrial Thermal Spray Coatings Using a Modified Layer-Removal Method. Journal of Thermal Spray Technology, 3, pp.379–388. Available at: https://doi.org/10.1007/BF02658983.

Hobbs, M.K. & Reiter, H. 1988. Residual Stresses in ZrO2-8%Y2O3 Plasma-Sprayed Thermal Barrier Coating. Surface and Coatings Technology, 34(1), pp.33–42. Available at: https://doi.org/10.1016/0257-8972(88)90086-2.

Kesler, O., Matejicek, J., Sampath, S., Suresh, S., Gnaeupel-Herold, T., Brand, P.C. & Prask, H.J. 1998. Measurement of Residual Stress in Plasma- Sprayed Metallic, Ceramic and Composite Coatings. Materials Science and Engineering A, 257(2), pp.215–224. Available at: https://doi.org/10.1016/S0921-5093(98)00860-0.

Limarga, M.A., Vaßen, R. & Clarke, R.D. 2011. Stress Distributions in Plasma-Sprayed Thermal Barrier Coatings Under Thermal Cycling in a Temperature Gradient. Journal of Applied Mechanics, 78(1). Available at: https://doi.org/10.1115/1.4002209.

Matejicek, J., Sampath, S., Brand, P.C. & Prask, H.J. 1999. Quenching, Thermal and Residual Stress in Plasma Sprayed Deposits: NiCrAlY and YSZ Coatings. Acta Materialia, 47(2), pp.607–617. Available at: https://doi.org/10.1016/S1359-6454(98)00360-7.

Miyazaki, H., Ushiroda, I., Itomura, D. & Ota, T. 2008. Thermal expansion of hydroxyapatite between -100 °C and +50 °C. Materials Science and Engineering C, 29(4), pp.1463-1466. Available at: https://doi.org/10.1016/j.msec.2008.12.001.

Mrdak, M.R. 2017. Testing mechanical structural characteristics of Al2O3 oxide ceramics resistant to sliding friction, Vojnotehnički glasnik / Military Technical Courier, 65(4), pp.924-936. Available at: https://doi.org/10.5937/vojtehg65-12000.

Otsubo, F., Kishitake, K. & Terasaki, T. 2005. Residual Stress Distribution in Thermally Sprayed Self-Fluxing Alloy Coatings. Materials Transactions, 46(11), pp.2473-2477. Available at: https://doi.org/10.2320/matertrans.46.2473.

Rickerby, D.S., Scott, K.T., Eckold, G. & Lloyd-Thomas, D. 1988. Analysis of the Residual Stresses in Plasma Sprayed Coatings. In 1st Plasma-Technik-Symposium, Swicerland, Lucerne, pp.267-276. May 18-20.

Teixeira, V., Andritschky, M., Fischer, W., Buchkremer, H.P. & Stöver, D. 1999. Analysis of Residual Stresses in Thermal Barrier Coatings. Journal of Materials Processing Technology, 92–93, pp.209–216. Available at: https://doi.org/10.1016/S0924-0136(99)00157-0.

Zhu, J.G., Xie, H.M., Li, Y.J., Hu, Z.X., Luo, Q. & Gu, C.Z. 2014. Interfacial Residual Stress Analysis of Thermal Spray Coatings by Miniature Ring-Core Cutting Combined with DIC Method. Experimental Mechanics, 54(2), pp.127–136. Available at: https://doi.org/10.1007/s11340-012-9640-2.

Zhuang, H. & Gu, G. 1988. A Study on Residual Stress of ZrO2+MgO Plasma Sprayed Coating. In 1st Plasma-Technik-Symposium, Swicerland, Lucerne, pp.277-284. May 18-20.

Published
2018/09/03
Section
Professional Papers