Plasma of electric arc between one-component Cu and Ni and composite Ag-Ni electrodes was studied by means of optical emission spectroscopy. Radial temperature profiles of plasma column were obtained using Boltzmann plot techniques at arc currents of 3.5 and 30 A. Radial distributions of plasma electron density of electric arc discharge between Cu and Ni and Ag-Ni electrodes were measured as well at currents 3.5 and 30 A. Equilibrium of plasma composition was calculated. The properties of material erosion processes on the electrodes" surface are studied.
