Effects of As-Cast Surface Conditions and Local Geometry on Plating Deposition

The inhomogeneity of casting microstructure can present many challenges to subsequent processing of castings such as electroplating. Specifically the surface microstructure and local topographic features have significant impact on the electroplating deposition thus the continuity of the plating films. The authors attempt to categorize the common casting surface microstructure features and correlate them to the electroplating characteristics such as conductivity and current density distribution, which in turn affect the plating deposition. Forming mechanisms of some of the most common casting surface microstructures that affect electroplating are discussed. Desirable casting surface microstructure for electroplating and the casting design and process practices to achieve it are proposed.