Journal of Thermal Spray Technology

, Volume 16, Issue 5, pp 933–939

Detection of Wear in One-Cathode Plasma Torch Electrodes and its Impact on Velocity and Temperature of Injected Particles

  • Georg Mauer
  • José-Luis Marqués-López
  • Robert Vaßen
  • Detlev Stöver
Peer Reviewed

DOI: 10.1007/s11666-007-9094-8

Cite this article as:
Mauer, G., Marqués-López, J., Vaßen, R. et al. J Therm Spray Tech (2007) 16: 933. doi:10.1007/s11666-007-9094-8

Abstract

Wear at the electrode surfaces of a one-cathode plasma torch changes the characteristic fluctuation pattern of the plasma jet. This affects the trajectory of the particles injected into the plasma jet in a non-controllable way, which degrades the reproducibility of the process. Time-based voltage measurements and Fourier analysis were carried out on a one-cathode F4 torch at different wear conditions to determine the evolution of wear dependant characteristics. A significant correlation is observed between increasing torch wear and decreasing voltage roughness and high frequency noise. Furthermore, by means of particle diagnostic systems, the change in the particle velocity and temperature has been measured. The variations of the particle characteristics are significant and thus an influence on the sprayed coating microstructure is to be expected.

Keywords

electrodeparticle diagnosticsplasma sprayingprocess monitoringtorchvoltagewear

Copyright information

© ASM International 2007

Authors and Affiliations

  • Georg Mauer
    • 1
  • José-Luis Marqués-López
    • 1
  • Robert Vaßen
    • 1
  • Detlev Stöver
    • 1
  1. 1.Institut für Energieforschung IEF-1, Forschungszentrum Jülich GmbHJülichGermany