Suppression of core-corona structure in single-wire aluminum Z-pinches

The circuit and load parameter ranges, in which gaseous aluminum other than core-corona structures could be obtained from the single aluminum wire Z pinch, were analyzed by thermodynamical model. Firstly, the energy deposition criterion and the voltage breakdown criterion were proposed. Secondly, thermodynamical models were established. The circuit parameters were determined by ensuring a rapid decrease of the load current when the wire turns to gas in order to avoid electrical voltage breakdown. Finally, the load current voltage, resistance, and the deposited energy were calculated, and their dependences on the circuit inductance, charging voltage, and wire diameter were analyzed. The calculation results indicated that with a storage capacitance of 150 nF, a charging voltage of 65 kV, and a loop inductance of 300 nH, an aluminum wire of a length of 2 cm and a diameter of 20 μm could be heated to gas state. A faster rising current, a smaller wire diameter or little length would enhance the energy deposition in the wire, and are easier to produce gaseous aluminums. (authors)