Shock wave characteristics generated by electrical explosion of different wires in water

Summary form only given. Underwater electrical wire explosion could be an optimal way to produce partially controllable shock waves, thus becoming a promising method for breaking stones, exploiting related applications, etc. The mechanisms of forming shock waves by utilizing electrical explosion of thin metal wires in various media might be sophisticated, with several processes demanding to be considered. It could be known that both phase transition and expansion of discharge channel contribute to shock waves' formation according to previous researches. Therefore, different wire materials or circuit parameters would definitely have influences on the shock waves. However, precise quantitative calculation might be relatively difficult. Al, Cu, W, W-Re, Mo, Ni, Ti, Fe, Ta, and Nb wires were exploded by microsecond timescale pulsed current peaking at ~50 kA in water. The platform contained a 6 μF pulse capacitor with an initial voltage of 25 kV. Shock wave waveforms were recorded by PCB 138A piezoelectric probes and PVDF probes. Time of flight method was also adopted to calibrate the probes. Peak pressure, impulse, and other related parameters were analyzed. The results showed the materials do have influence on the shock waves. For instance, with same storage energy, although shock waves generated by Cu and Mo wire could have comparable peak pressure, the impulse could have an evidently difference (Mo's was larger), which might be caused by the phase explosion. However, it is quite hard to control variables of the wires and a more systematical group of experiments would be indispensable in the following studies.