Home
For authors
Submission status

Current
Archive (English)
Archive
   Volumes 81-92
   Volumes 41-60
   Volumes 21-40
   Volumes 1-20
   Volumes 61-80
      Volume 80
      Volume 79
      Volume 78
      Volume 77
      Volume 76
      Volume 75
      Volume 74
      Volume 73
      Volume 72
      Volume 71
      Volume 70
      Volume 69
      Volume 68
      Volume 67
      Volume 66
      Volume 65
      Volume 64
      Volume 63
      Volume 62
      Volume 61
Search
VOLUME 73 (2001) | ISSUE 2 | PAGE 74

Homogeneous electrical explosion of tungsten wire in vacuum
PACS: 52.80.Qj
Abstract
Experimental results on joule energy deposition at initiation of a fast electrical explosion of 16μm tungsten wire in vacuum at current densities of more than 108 A/cm2 are reported. We find that explosion with a fast current rise-time (\sim170 A/ns into a short) results in homogeneous and enhanced deposition of electrical energy into the tungsten before surface flashover. The maximum tungsten wire resistivity reaches the value of up to \sim185\mu\Omega cm before surface flashover that significantly exceeds the melting boundary and corresponds to temperature of \sim1 eV. The highest values for light radiation and expansion velocity of wire \sim1 km/s have been observed for the fast explosion. For the explosion mode with a slower current rise-time (\sim20 A/ns into a short)), we observe the existence of an "energy deposition barrier" for tungsten wire. At slow explosion mode the current is reconnected to the surface shunting discharge before melting. The maximum tungsten wire resistivity in this case reaches the value of \sim120 \mu\Omega\cdotcm which is less than indicative of melting. Also the energy deposition along the wire is strongly inhomogeneous and wire is disintegrated into parts. We attribute the early reconnection of the current to the surface discharge for the slow explosion to high electronic emission from the wire surface, which starts before melting.