镁合金化学镀镍层的生长过程

The initial nickel deposition for the direct electro le ss nickel plating on non-catalytically active magnesium alloy is critical.The s urface morphology and composition of the initial nickel plating coating are obta ined by means of the scanning electron microscopy (SEM) and the energy dispersiv e X-ray (EDS).In addition, the mass gain/loss in the initial nickel deposition process was measured by using the electro-balance.The results showed that the M gO coating was gradually corroded by the plating solution, at the same time, MgF 2 produced by F-,H+ and MgO was deposited on the substrate during the init ial electroless plating process.The nickel of the initial electroless plating wa s mostly growing on the boundary between the MgF 2 coating and the MgO coating of the activation substrate, and then came to two sides.After that, the Ni-P co ating growth rate to cover with the MgF 2 coating was prior to the MgO coating. The electroless plating was in company with the substrate corrosion,but the elec troless plating rate catalyzed by the exchanged nickel was more than the substra te corrosion rate.