Electric Explosion of Fine Tungsten Wires in Vacuum

A study is made of the breakdown of a fine wire during its electric explosion in vacuum. The problem of how the wire diameter, the rate of energy deposition in the wire, and the insulation of the electrode surface near the electrode-wire contact influence the wire explosion and the accompanying breakdown is investigated experimentally. The wire explosion was performed at a positive polarity of the high-voltage electrode. A current density growth rate of 6 x 1011-5 x 1016 A/(s cm2) is achieved. It is shown that the breakdown along a wire is similar in many respects to the gas breakdown. The insulation of the wire surface makes it possible to avoid breakdown and to increase the deposited energy to values sufficient for the wire sublimation