Fig. 1. Schematic of switch of experiment circuit

Fig. 2. Typical waveforms of circuit current and voltage in trigger electrode

Fig. 3. Relation ships between self-breakdown voltages and discharge times

Fig. 4. Variation trend of trigger time delay of intermediate electrode stainless steel and brass

Fig. 5. Macrographs of stainless steel and brass electrode surfaces after 2 400 discharges

Fig. 6. Surface microstructure of stainless steel and brass anode

Fig. 7. Actual contours of anode and cathode after different discharge times (stainless steel electrodes)

Fig. 8. Actual contours of anode and cathode after different discharge times (brass electrodes)

Fig. 9. Variation of surface roughness of intermediate electrode