Study on Electrod Consumption in Air Plasma Arc

New Cathode Material for Air Plasma Cutting (Report 6)

Abstract

This paper describes the affection of O₂ and N₂ gases in operating gas on the electrode consumption for air plasma cutting, and discusses on the consumption mechanism of the developed new electrodes.
From the consumption test under various shielding gases, it is concluded: Ru-Y₂O₃ and Ir-Y₂O₃ electrodes showed a good erosion resistance in oxidizing atmosphere (O₂, Air), however these electrodes showed extremely increased weight loss in non-oxidizing atmosphere (At, N₂). The characteristic of Ru-Y₂O₃ and Ir-Y₂O₃ electrodes is discussed from the qualitative model that the formation and evaporation of Y₂O₃ layer covered the cathode surface occurs.