An experimental study on correlation between electromagnetic noise and trace of discharge in Cu-C electrodes-case of C (anode)-Cu (cathode)

The authors observed the correlation between electromagnetic noise and trace of discharge on surface in opening carbon(C)-copper(Cu) electrodes. In the case of C (anode)-Cu (cathode), continuous burst noise is generated over the period of arc discharge. When the discontinuous fluctuation of arc voltage occurs, the level of burst noise becomes high in that period. Arc discharge is classified into four periods based on features of the arc voltage and the burst noise waveforms. There are circular traces of discharge (area α) and a shiny melted area (area β) on the electrode surface. When the period of high noise level becomes longer, area α has wide distribution on the surface. When the period of low noise level in the middle of the arc becomes longer, area β distributes widely. The period of low noise level in the start of the arc has small correlation with the area α, β. From these results, it is considered that arc discharge of three different types are mixed in one opening period of electrodes