Study on the corrosion resistance and the wear resistance of electroless nickel plating of magnesium alloy

The coatings containing different phosphor content were prepared by the process of electroless nickel plating on magnesium alloy, and the samples containing high, middle and low phosphor content were heat treated at different temperatures. The effect of phosphor content and treatment temperature on the microstructure of coating was studied using SEM and X-ray. and their effects on the corrosion and wear resistance of coatings were also investigated by comparing their polarization curves and wear tests on a M-200 model testing machine respectively. The experimental results showed that the microstructure of coating was transformed from crystal into amorphous state, the corrosion resistance was improved and the wear resistance decreased with increase of phosphor content. For high phosphor coating, the microstructure of coating could be transformed from amorphous into crystal state during heat treatment. separating out Ni3P and Ni phases, the wear resistance was increased and the corrosion resistance was reduced with increase of heat treatment temperature.