Among electrical contact materials, AgW and AgWC electrical contacts are widely used as movable contacts in various circuit breakers due to their good electrical conductivity, electrothermal properties, and good electrical wear resistance. However, in recent years, with the continuous improvement of the use requirements of circuit breakers, especially in harsh environments, higher requirements have been placed on the corrosion resistance of electrical contact materials. In addition to electroplating a silver layer on the surface of electrical contacts, directly exuding a layer of silver on the surface during the contact manufacturing process is also a method. Recently, there is also research on improving the corrosion resistance of AgW by adding additives.
The study compared the corrosion resistance of AgW and AgWC electrical contacts using powder metallurgy infiltration technology in high and low temperature alternating humid heat and salt spray environments to clarify the strength of their corrosion resistance.
① In the high and low temperature humidity alternating test
The oxidation rate of AgW electrical contacts without additives is the fastest, and the oxidation rate of AgW electrical contacts with additives is slowed down. As the content of additives increases, the oxidation rate becomes slower; the AgWC electrical contacts still remain stable after 14 test cycles. No signs of oxidation were found.
The results show that the corrosion resistance of AgWC electrical contacts is significantly better than that of AgW electrical contacts.
② In salt spray test
Neither the AgW electrical contacts nor the AgWC electrical contacts were significantly oxidized after the 240 h test.
The results show that the corrosion resistance of AgW and AgWC electrical contacts is equivalent.
——The content of the article comes from the Internet