THE TEMPERATURE OF A PLASMA USED IN ELECTRICAL-DISCHARGE MACHINING

The temperature in an electrical discharge machining (EDM) plasma was determined from measurements of relative intensities of the 411.85 and 413.29 nm Fe I spectral lines. The time-dependence of the plasma temp erature was measured for individual electrical machining pulses. Under our experimental conditions (electrodes of NC6(+) and M1E(-), cosmeti c paraffin as the dielectric liquid) the measured plasma temperature r anged from 8000 to 10 000 K for different current pulses. We observed higher temperature values during the initial phase of the discharge. T emporal characteristics of discharge electric parameters, light emissi on and the plasma temperature are presented.