1. Function and Characteristics: Nickel plating is used as a substrate coating for precious and base metals on printed circuit boards (PCBs), and is also commonly used as a surface layer for some single-sided PCBs. The manufacturer tells you that for some surfaces with heavy load wear, such as switch contacts, contact pads, or plug gold, using nickel as the substrate coating for gold can greatly improve wear resistance. When used as a barrier layer, nickel can effectively prevent diffusion betwe...