A fundamental study on effect of contact condition for electromagnetic noise at copper-carbon electrodes

The authors observed the correlation between electromagnetic noise and trace of discharge on surface for various surface areas of Cu in opening copper (Cu)-carbon (C) electrodes. In the case of Cu (anode)-C (cathode), the duration of sporadic burst noise generated by discharge becomes longer when Cu surface area is increased, and trace of discharge (melting area) distribute widely on electrodes. Also the forms of the burst noise in the start of arc are classified, and the traces of discharge correspond to each forms. The forms of the burst noise depend on the pattern which the trace of discharge are formed. As these results, the authors showed the correlation between form of burst noise and trace of discharge on electrode surface.