title: Transformation of a tungsten wire to the plasma state by nanosecond electrical explosion in vacuum.
abstract: Experiment demonstrates the first direct transformation of a tungsten wire core to the plasma state by Joule heating during nanosecond electrical explosion in vacuum. Energy of approximately 130 eV/atom was deposited into the 12 microm W wire coated by 2 microm polyimide during the first approximately 10 ns. All the metal rapidly transformed to highly ionized plasma, while the surrounding polyimide coating remained primarily in a gaseous state. This coating totally suppressed corona formation. The expansion velocity of the wire was approximately 12-18 km/s, the average wire ionization at 50 ns reached approximately 67% with corresponding LTE temperature of approximately 1.2 eV . Explosion of bare W wire demonstrated earlier termination of the wire core heating due to shunting corona generation. Magnetohydrodynamic (MHD) simulation reproduces the main features of coated and uncoated W wire explosion.
authors.affiliation: Ktech Corporation, Albuquerque, 10800 Gibson Blvd., New Mexico 87123, USA.
authors.forename: G S
authors.initials: GS
authors.lastname: Sarkisov
authors.forename: S E
authors.initials: SE
authors.lastname: Rosenthal
authors.forename: K W
authors.initials: KW
authors.lastname: Struve