Bimolecular mechanism of electroless coating of magnesium alloys

This paper deals with the study of possible mechanism of electroless nickel plating. Magnesium alloy AZ91 was used as a substrate for electroless deposition of Ni-P coating. The primary objective of the research was the optimization of plating process for this alloy. During the optimization of nickel plating in case of the sample B23, the half- amount of reducing agent was used. Previous research in this field assumed monomolecular mechanism which corresponds to a first order reaction. All Ni-P coatings were analysed by EDS at scanning electron microscope and the content of phosphorus and nickel was estimated. Calculations were then performed that confirmed decrease of ratio Ni /P in the coatings by one quarter. This could correspond to bimolecular mechanism of electroless nickel plating.