Technological Aspects of the Nanocomposite Silver-Based Contact Material

摘要

The research works carried out at the Institute of Non-Ferrous Metals, which were related to fabrication of the composite contact materials AgSnO_2Bi_2O_310 from solid semiproducts having a form of wires and strips, and from the AgSn7.5Bi0.4 powders or a mixture of pure Ag powder with nanopowders of the oxides of tin and bismuth, have been presented. Based on the results from these works it has been concluded that the most beneficial and optimal method for fabrication of these composite contact materials was the powder metallurgy based process used to produce AgSnBi-type materials. This technology includes isostatic compacting of the powders, their internal oxidation and plastic consolidation by hydrostatic extrusion. The nanocomposite contact material obtained by this method, typically in a form of wires and contact rivets, is characterized by high physical, mechanical and functional properties. The paper presents detailed results of the technological tests aimed at fabricating sample batches of wires and bimetallic contact rivets and at determining contact life of the electric relays incorporating bimetallic contacts made from the newly developed nanocomposite material.