Technology for Direct Electroless Nickel Plating on AZ91D Magnesium Alloy

The technology for direct electroless nickel plating on AZ91D Mg alloy was studied. The surface morphologies of Mg alloy after pre-treatment electroless nickel plating and direct electroless nickel plating were analyzed,and the effect of electroless plating conditions on the morphology of the Ni-P coating was explored. The adhesion of the coating to Mg alloy substrate and the microstructure of the coating were measured. Results show that smooth and compact amorphous Ni-P alloy coating with high hardness and good adhesion to substrate can be prepared on Mg alloy via direct electroless Ni plating in a NiSO4 bath with a pH value of 5.5～6.5 and temperature of 80～95 ℃ for 1.0~2.5 h.