Copper cathode erosion by an electric arc - the causes of the variations of the erosion rate with the electrode gap
Résumé
In this paper we present a study concerning the influence of the electrode gap on the erosion of a copper cathode under the sole action of an electric arc in air at atmospheric pressure. The causes of the variations of the erosion rate with this parameter are studied. It is shown that, certainly, the variations of the erosion rates with the electrode gap should be imputed to two factors: the arc mobility which changes strongly with the electrode gap and a `supplementary' heating of the cathode surface due to interactions that occur at small electrode gap values between the cathode surface and the anode plasma jets.