Electroless Nickel Deposition on Dual Phase Structure of LZ91 Mg-Li Alloy

The surface morphology of Mg-Li alloy after electroless nickel deposition for different periods of time was observed by scanning electron microscopy, element distribution on the surface was analyzed using energy dispersive spectroscopy. The activation products were analyzed by X-ray photoelectron spectroscopy (XPS), and the deposition process of electroless nickel deposition on the surface of two-phase structure was studied. The results show that the activation products were different on the surface of two-phase (α phase and β phase) microstructure of Mg-Li alloy during the activation process. The content of soluble substances such as LiOH and LiF on the surface of the β phase was significantly higher than that on the surface of the α phase, resulting in the deposition process starting from the β phase surface and then on the α phase surface. In the deposition process, Ni was deposited at first by substitution reaction, and then Ni-P was deposited by autocatalytic reaction.