Electrochemical Dissolution Behavior of ZCuPb10Sn10 Alloy in NaNO3 Solution

Copper alloys, such as ZCuPb10Sn10, have been widely applied to friction pairs in various products. Surface texture, such as micro-dimple array has attracted significant attention from researchers worldwide to improve tribological performance. To generate micro-dimple array on ZCuPb10Sn10 alloy by electrochemical machining, it is essential to investigate the electrochemical dissolution behavior of ZCuPb10Sn10 in NaNO₃ solution. In this paper, the electrochemical dissolution behavior of ZCuPb10Sn10 alloy in NaNO₃ solution is investigated through experimental tests. Anodic polarization, Tafel polarization, and electrochemical impedance spectroscopy were conducted to investigate its passive and corrosion behavior. The microstructure and composition of the dissolved surfaces were analyzed under various conditions. Additionally, a model was proposed to explain the electrochemical dissolution process of ZCuPb10Sn10 alloy in NaNO₃ solution under high pressure hydrostatic conditions. Ultimately, a NaNO₃ solution with 10% in concentration and 20 °C in temperature was selected as the electrolyte and a micro-dimple array with an average diameter of 119.7 μm and a depth of 7.4 μm was successfully generated with through-mask electrochemical micromachining on the surface of ZCuPb10Sn10 alloy.