Effect of Medium on Deposited Energy in Microsecond Electrical Explosion of Wires

The properties of the medium have an obvious effect on the process of the electrical explosion of the wire. In this paper, the electrical explosions of copper and aluminum wires were investigated in air and water with pulsed voltage in a time scale of a few microseconds. Based on the measurements of the current and voltage waveforms in wire explosion with a self-integrating Rogowski coil and a voltage divider, respectively, the deposited energy in the stages of melting, liquid state, and vaporization was calculated by mathematical method. The effect of air and water on deposited energy in the three stages previously mentioned was analyzed by experiments and calculation. The results show that the pressure of the medium around the wire generated by compression from wire material expansion is an important factor of the effect of the medium on the energy deposition and the time of duration in the different stages. Additionally, the species of the medium also has an important effect on the formation of plasma discharge channel. The deposited energy in the electrical explosion of copper and aluminum wire in water is more than that in air, particularly after the beginning of vaporization.