Density Distribution of Plasma Species in a Hollow Cathode Arc Discharge for Coating Application

Abstract

The plasma of a hollow cathode arc discharge (argon/titanium) was studied by emission spectroscopy and probe measurements. The behavior of the relative particle concentrations of the different heavy plasma components as well as the concentration and temperature of the electrons was determined as function of the vertical distance from the anode crucible.Abel-inverted radial distributions of the relative level populations for Ti Z (neutral titanium), Ti IZ (singly ionized titanium), Ar Z and AT ZZ are presented. Further measurements characterize the influence of the discharge current on the relative level population.

Emission of charged particles from laser-induced germanium ecton, vacuum spark, and vacuum arc

“…If we take fp ≈ 8.98Z(ne) 1/2 (me/mi) 1/2 as an upper limit for the frequency with Z = 1.4 as the charge state, the ratio (me/mi) 1/2 = 1/365 as the electron-to-ion mass ratio, and an oscillation period of 400 ns, then the electron density of the arc in Fig. 4 can be calculated to be at least 5.27 x 10 15 m -3 , close to that of previous arc studies for similar current values [23,24].…”