Experimental study on effective emitting area of explosive emitting cathode

Variation relation between the effective emitting area of field induced explosive ementting graphite cathode and time has been acquired experimentally under different externally applied electric field corresponding to different anode cathode gaps. It is illustrated that the effective emitting area increase over time at the beginning of emission.The time for the effective emitting area to reach 1.0 decreases with increasing mean electric field in the gap. Under approximate 100 kV/cm mean electric field between anode and cathode, about 20 ns is needed for the effective emitting area to reach 1.0. The relative delay time of effective emitting area reaching 0.5 to 50 % voltage pulse with the electric field behaves as a decaying exponential curve．