On the Issue of the Thermal Emission Cathode Resource on the Oxide Films of Hafnium and Zirconium

Authors

  • M. Klochok Taras Shevchenko National University of Kyiv, Volodymyrska Street 64/13, 01601, Kyiv
  • Y. Popil Kiev National Technical University, Docent
  • V. Chernyak Taras Shevchenko National University of Kyiv, Volodymyrska Street 64/13, 01601, Kyiv
  • V. Iukhymenko Taras Shevchenko National University of Kyiv, Volodymyrska Street 64/13, 01601, Kyiv
  • I. Fedirchyk Taras Shevchenko National University of Kyiv, Volodymyrska Street 64/13, 01601, Kyiv
  • V. Tkach V. Bakul Institute for Superhard Materials NASU, Avtozavodska Street 2, 04074, Kyiv

DOI:

https://doi.org/10.14311/ppt.2019.3.247

Keywords:

plasma, surface scanning, erosion, erosion mass, attachment spot

Abstract

The article shows the results of research on the destruction of the thermionic cathode of an arc plasma torch when inserting hafnium and zirconium along the trace of the spot of a gas-discharge arc by means of electronic metallography with spectral analysis in the control region. The depth of penetration of the spot into the metal of the cathode insert was determined due to the discrete mechanism of action on the metal at the time of attachment. The erosion rate of zirconium oxide films was experimentally established, the extension of the operating life substantiated while mechanisms for its increase were revealed, and two types of arc contact with a hafnium or zirconium insert - the "contracted" and "diffused" ones - were offered. The theoretical operating life of the cathode is calculated.

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Published

2019-11-29

Issue

Vol. 6 No. 3 (2019)

Section

Articles

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