Influence of the Motion Dynamics of Electric Arc's Near-Electrode Region on Erosion in a Two-Chamber Anode

The article presents an experimental study of the dynamics of movement of arc anode region in a two-chamber electrode and its erosion in the speed range from 40 to 76 m/s. We have investigated the shape of the radial section of electric arc column for different motion speeds of its anode region. There is a U-shaped dependence of two-chamber anode erosion from the motion speed of near-electrode region of the arc. It has been established the existence of a critical speed of electric arc spot movement, above which a sharp increase in the level of specific erosion of the anode occurs, and at a speed of its movement above the critical one we observe a microscale shunting in near-electrode region of the arc. The scale of the shunting process is approximately equal to the diameter of near-electrode section of the arc column, and the frequency is tens of kilohertz. At a speed of arc’s anode region below the critical one, it continuously moves along the surface of the electrode.