The Effects of Preheating of a Fine Tungsten Wire and the Polarity of a High-Voltage Electrode on the Energy Characteristics of an Electrically Exploded Wire in Vacuum

Results obtained from experimental and numerical studies of tungsten wires electrical explosion in vacuum are presented. The experiments were performed both with and without preheating of the wires, using positive or negative polarity of a high-voltage electrode. Preheating is shown to increase energy deposition in the wire core due to a longer resistive heating stage. The effect was observed both in single wire and wire array experiments. The evolution of the phase state of the wire material during explosion was examined by means of one-dimensional numerical simulation using a semiempirical wide-range equation of state describing the properties of tungsten with allowance made for melting and vaporization.