Ni-W alloy eiectrodeposition from a bath containing an organic amine substitute for inorganic ammonia

In this work, a simple organic amine, glycine, was used as a substitute for inorganic ammonia salts or free ammonia, which are generally used in nickel-tungsten (Ni-W) alloy electrodeposition. The results indicated that glycine was more effective in increasing deposition efficiency. However, it also reduced the tungsten content, when compared with results from inorganic ammonia systems, all other plating parameters being the same. Therefore - glycine functioned similarly. Glycine however, forms a stronger complex with nickel ions than does NH₃ and it has a completely different hydrolysis mode. Thus the deposition behavior from a solution containing glycine was somewhat different. Accordingly, we studied the effects of bath pH and glycine concentration. A significantly different structure was found in the Ni-W alloy deposited from the glycine-containing bath.