The Effect of Temperature on Wear Resistance and Behavior of Pure Silver and Silver/Silver-Graphite Composite Coatings Prepared by Electro-Deposition

The pure silver and silver/silver-graphite composite coatings on the substrate of copper were prepared by electro-deposition. The wear resistance and behavior of the pure silver and silver/silver-graphite composite coatings at different processing temperature were investigated. The wear mechanism of pure silver coating at room temperature to 120 ℃ was the mild adhesive wear, the friction coefficient and wear rate was about 0.35~0.45 and 3×10^-14 m³/(N·m), respectively. At 240~480 ℃, the wear mechanism of pure silver coating was adhesive wear and its wear rate increased rapidly and friction coefficient was instable. The wear mechanism of pure silver/silver-graphite composite coating at room temperature to 240 ℃ was the mild adhesive wear, its friction coefficient was about 0.1 and wear rate increased slowly with temperature. At temperature between 240 ℃ and 480 ℃, the severe plastic deformation appeared on the composite coating due to the fracture of the graphite film at high temperature. At 480 ℃, the wear mechanism of composite coating was mainly abrasive wear, its friction coefficient was instable and the wear rate of the composite coating was 46×10^-14 m³/(N·m), indicating the wear resistance of high temperature was better than that of the pure silver coating.