CORROSION BEHAVIOR OF ELECTRODEPOSITED ZINC-NICKEL ALLOYS

Improved corrosion resistance requirements, higher production costs and stringent pollution regulations have led researchers and commercial platers to study and develop new types of coatings for protection of steel components. Deposition of zinc-nickel alloy is of particular interest to the automobile industry where the coatings should satisfy many vital requirements such as formability, weldability, paint adhesion. This paper discusses the corrosion behaviour of zinc-nickel alloy coatings of various thicknesses and different compositions in the chromated and non-chromated condition on steel. The corrosion resistance was tested by various electrochemical methods and an industrially adopted salt spray test and the results indicate that an alloy deposit containing 15-18% nickel can efficiently replace zinc and cadmium deposits.