Development of tungsten high-current contacts based on metalworking wastes

Abstract

For the manufacture of pseudo-alloys of the tungsten-copper system, which are used in the electrical industry for high voltage conditions, powder metallurgy technologies are promising. Moreover, due to the large difference in the melting temperatures of the main components, the porous skeleton of the refractory component (W) is poorly leaked by the copper melt due to its low wettability. To eliminate this drawback, additional alloying is used with elements of group VIII of the Periodic system - nickel or cobalt, which significantly increases the cost of products.
In the work, it is proposed to use metalworking wastes of heavy residence permits alloys in the form of shavings and copper wastes in the form of a ground rod to create highly current contacts.. The effect of pressure on the compaction of tungsten-based alloy shavings is investigated. The technology of impregnating copper with porous frames of heavy alloy was developed. Studies of the macrostructure of composites showed that after the briquettes are impregnated, a skeleton structure of a residence permit alloy with copper layers is formed. The interaction between the frame and the copper melt is established, which is ensured by nickel and iron, which are part of the tungsten-based heavy alloy. The results of testing the erosion rate showed that fragmentation of the composite material in the case of approved electric arcs on the level of standard pseudo-alloys. The possibility of cheapening the technology for producing pseudo-alloys for high current contacts is shown to have a low electrical resistivity and high values of erosion resistance.