ELECTRIC CONTACTS FOR ELECTROTECHNICAL APPARATUS WITH VACUUM SWITCH AND

The invention refers to electrical contacts of tungsten, copper-nickel pseudo-alloys, with antimony in nut, with high electrical and thermal conductivity, resistance to electric arc, resistance to welding and minimum content of gases, minimum "current cut", meeting the requirements imposed to contact materials for commutation in vacuum.The production procedure of the tungsten-copper-nickel contacts with antimony in nut for vacuum commutation based on methods of the powder metallurgy consists of: sintering in hydrogen of compressed pellets of tungsten with a porosity corresponding to the desired content of copper; infiltration of these pellets with copper-nickel, by their heating together with raw pellets of copper-nickel at temperatures above the liquids curve of the binary copper-nickel alloys in vacuum; incorporation of antimony in a nut applied to the contact surface by heating the contacts with the nut filled with antimony powder or with a corresponding pellet pressed from antimony powder at temperatures above the melting point of the antimony, in argon.