The Preparation of Silver-Coated Nickel Powders via Electroless Plating

A novel method via electroless silver coating on nickel powders was reported., which introduced reduction reaction using hydrazine as the reducing agent, had some advantages such as inhibiting the substitution reaction and reducing consumption of nickel powders. In the process of dispersion, PVP acted as the dispersant and prevented the nickel powders from agglomerating.The Zeta potential of slurry which determined the dispersibility and the reaction condition was tested.The investigation shows that the grain size of Ag-Ni bimetallic powders is similar to the nickel powders, bimetallic powders possesses fine dispersibility and a continuous silver film is formed on the surface of nickel powders by two-times coating. Morphology of Ag-Ni bimetallic powders, composition of the coated-surface are respectively characterized by SEM and EDX.