The Corrosion Behavior of Different Silver Plating Layers as Electrical Contact Materials in Sulfur-Containing Environments

Isolation switching devices are vital components in power grids. During their operational lifespan, these devices are prone to corrosion failure in atmospheric environments. To enhance conductivity and corrosion resistance, silver plating is applied to the contact surface of high-voltage switches. Common methods include graphite-Ag (G-Ag) coating, graphene-Ag (Gr-Ag) coating, and Ag-Sn coating. In this article, the corrosion resistance performance of silver plating, G-Ag coating, Gr-Ag coating, and Ag-Sn coating was studied. Firstly, adhesion tests were conducted on the plating layers. Subsequently, immersion experiments were performed to evaluate the corrosion resistance of the samples. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and laser confocal microscopy were used to analyze the morphology and elemental composition of the samples. Raman spectroscopy was used to analyze corrosion products. An electrochemical workstation was employed to study the electrochemical behavior of the samples. The adhesion results indicate that the adhesion of the plating layers is excellent. The immersion and electrochemical results showed the corrosion resistance order of the four Ag coatings was Ag-Sn coating > Gr-Ag coating > Ag coating > G-Ag coating.