Skip to main content
Log in

Analysis of the nonthermal emission signal present in a molybdenum particle-laden plasma-spray plume

  • Revieweed Papers
  • Published:
Journal of Thermal Spray Technology Aims and scope Submit manuscript

Abstract

In-flight measurement of the surface temperature of plasma-sprayed particles is important for the correlation of particle characteristics to coating structure and properties. However, the use of optical pyrometry for particle surface temperature measurement has inherent uncertainties due to nonthermal emission signals in the plasma/particle plume. This nonthermal signal is especially bothersome near the torch exit and in regions of the plume where there are few particles. This work presents measurements of the nonthermal signals present when making temperature measurements of plasma-sprayed molybdenum particles. Changes in the nonthermal emission signals were found to be caused by particle vapor, the spectral plasma loading effect, and particle reflection of plasma light. Care must be taken to avoid particle temperature errors due to these effects.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. M. Vardelle, A. Vardelle, A.C. Leger, and P. Fauchais, Dynamics of Splat Formation and Solidification in Thermal Spraying Process, Thermal Spray Industrial Applications, C.C. Berndt and S. Sampath, Ed., ASM International, 1994, p 555–562

  2. R. McPherson, A Review of Microstructure and Properties of Plasma Sprayed Ceramic Coatings, Surf. Coat. Technol., Vol 39 (No. 40), 1989, p 173–181

    Article  Google Scholar 

  3. J. Mishin, M. Vardelle, J. Lesinski, and P. Fauchais, Two-Colour Pyrometer for the Statistical Measurement of the Surface Temperature of Particles Under Thermal Plasma Conditions, J. Phys. E. Sci. Instrum., Vol 20, 1987, p 620–625

    Article  CAS  Google Scholar 

  4. S. Kuroda, T. Fukushima, S. Kitahara, H. Fujimori, Y. Tomita, and T. Horiuchi, Monitoring of Thermally Sprayed Particles Using Thermal Radiation, Vol 2, Paper 27 of Proc. of 12th Int. Conf. on Thermal Spraying, I.A. Buckow, Ed., The Welding Institute, Cambridge, UK, 1989

    Google Scholar 

  5. J.R. Fincke, W.D. Swank, and C.L. Jeffery, Simultaneous Measurement of Particle Size, Velocity, and Temperature in Thermal Plasmas, IEEE Trans. on Plasma Sci., Vol 18 (No. 6), 1990, p 948–957

    Article  CAS  Google Scholar 

  6. K.J. Hollis and R.A. Neiser, Particle Temperature and Flux Measurement Utilizing a Nonthermal Signal Correction Process, J. Therm. Spray Technol., Vol 7 (No. 2), p 392–402

  7. K.J. Hollis and R.A. Neiser, Spectral Analysis of a Molybdenum Particle Laden Plasma Plume, Advances in Thermal Spray Science & Technology, C.C. Berndt and S. Sampath, Eds., ASM International, 1995, p 129–134

  8. T. Sakuta and M.I. Boulos, Novel Approach for Particle Velocity and Size Measurement Under Plasma Conditions, Rev. Sci. Instrum., Vol 59 (No. 2), 1988, p 285–291

    Article  Google Scholar 

  9. P. Gougeon and C. Moreau, In-Flight Particle Surface Temperature Measurements: Influence of the Plasma Light Scattered by the Particles, Thermal Spray Coatings: Research, Design and Applications, C. C. Berndt and T.F. Bernecki, Ed., ASM International, 1993, p 13–18

  10. J. Prucha and Z. Skarda, The Improvement of the Spectroscopical Temperature Diagnostic of Plasma Sprayed Particles, Thermal Spray: International Advances in Coatings Technology, C.C. Berndt, Ed., ASM International, 1992, p 343–348

  11. A.N. Zaidel’, V.K. Prokof’ev, S.M. Raiskii, V.A. Slavnyi, and E. Ya. Shreider, Tables of Spectral Lines, IFI/Plenum, 1970 (in Russian)

  12. M. Vardelle, C. Trassy, A. Vardelle, and P. Fauchais, Experimental Investigation of Powder Vaporization in Thermal Plasma Jets, Plasma Chemistry and Plasma Processing, Vol 11 (No. 2), 1991, p 185–201

    Article  CAS  Google Scholar 

  13. T.L. Eddy, B.A. Detering, and G.C. Wilson, LTE and Non-LTE Gas Temperatures in Loaded and Unloaded Plasma During Spraying of NiAl Powders, Thermal Spray Research and Applications, T.F. Bernecki, Ed., ASM International, 1990, p 33–37

  14. R.A. Neiser and T.J. Roemer, An Investigation of Particle Trajectories and Melting in an Air Plasma Sprayed Zirconia, Thermal Spray: Practical Solutions for Engineering Problems, C.C. Berndt, Ed., ASM International, 1996, p 285–293

  15. K.I. Lee, M. Vardelle, A. Vardelle, P. Fauchais, and C. Trassy, Vaporization of Metal Powders in Plasma Sprays, Thermal Spray: Practical Solutions for Engineering Problems, C.C. Berndt, Ed., ASM International, 1996, p 547–552

  16. J.R. Fincke and W.D. Swank, The Effect of Plasma Jet Fluctuations on Particle Time-Temperature Histories, Thermal Spray Coatings: Properties, Processes and Applications, T. F. Bernecki, Ed., ASM International, 1991, p 193–198

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Hollis, K., Neiser, R. Analysis of the nonthermal emission signal present in a molybdenum particle-laden plasma-spray plume. J Therm Spray Tech 7, 383–391 (1998). https://doi.org/10.1361/105996398770350864

Download citation

  • Received:

  • Revised:

  • Issue Date:

  • DOI: https://doi.org/10.1361/105996398770350864

Keywords

Navigation