Macroparticle dynamics in multi-cathode-spot (MCS) vacuum arcs were studied by utilizing laser Doppler anemomentry (LDA) methods for in situ measurement of the cathodic macroparticle velocities and relative emission rates. Arc current pulses having peak values of 1-2 kA at either 6 ms or 1 ms after arc initiation were investigated. Dependences of the macroparticle dynamics (i. e. speed and direction of flight) on cathodic thermophysical properties, location of the measurement probe in the interelectrode region, instantaneous value of the arc current, arc current waveform and macroparticle size were determined. It was found that the macroparticle velocity increased with distance from the cathode surface and with the instantaneous value of the arc current and decreased with macroparticle size and with the rise-time of the current wave form.
|Number of pages||4|
|State||Published - 1984|