Optical emission spectroscopy of breaking arc plasma between consumable electrodes

The investigation focuses on the optical emission spectroscopy of plasma generated by breaking arc between single-component Cu and composite Cu-W electrodes manufactured using shock sintering technology at temperature of 750°C. The electrodes were subjected to arc currents of 4, 50, and 104 A. Optical emission spectroscopy with high spectral and temporal resolution was employed to investigate the plasma with copper and tungsten vapour admixtures. The temporal evolution of temperature in the plasma was determined by the Boltzmann plot technique based on the emission intensities of Cu I spectral lines. Temporal evolution of electron densities were determined from the full width at half maximum of Cu I 515.3 nm spectral line. These initial plasma parameters integrated over the volume of breaking arc were utilized to calculate the temporal evolution of plasma compositions and contents of metal vapours admixtures in discharge gap.