High-power low-gas-pressure current switches

High-power low-pressure switches (pseudospark switches) for voltages of 1-45 kV and currents up to 150 kA are described. The maximum service life in terms of the switched charge is 10(5)-10(6) C. Examples of the cathode erosion depending on the operating conditions are presented. The principles of selecting the electrode material and design for improving the stability of the current pulse front and reducing the fatal erosion are shown. The structure of a sandwich-type cathode made of materials with different heats of sublimation and the construction of an efficient ignitor electrode, based on semiconducting boron nitrite-carbide, are described. The devices are used in industry (for magnetic-pulse, electrohydraulic, hydropulse, and laser treatment of materials), in oil production (for purifying oil-intake equipment and enhancing the discharge of oil wells by exciting intense shock waves during the electric discharge), in medicine (for noninvasive destruction of kidney stones, lithotripsy), in electrophysics and microelectronics in "plasma focus" installations thigh-power X-ray and neutron radiation sources), in accelerators of charged particles, etc.