Spectral characteristics of vacuum arc discharges with Ti and Zr cathodes

Spectroscopic study of two types of arc sources, used for industrial deposition of hard coating has been performed. The arcs with titanium and zirconium cathodes worked in vacuum, N2 or N2+C2H2 atmospheres. Atomic and molecular spectra excited in the arc discharges have been identified. Relations between spectral intensities of neutral (Ti I, Ar I, H, N2, CH) and ionised (Ti II, Ti III, Zr II, Zr III, Zr IV) species and current have been investigated at various experimental conditions. Spectroscopic characteristics of the discharges and mechanism of excitation have been discussed.