3.5. Microstructure of galvanic layer with sulfamate nickel intermediate layer
In the standard process, copper plating process is used. However, the tests of corrosion resistance in the salt chamber showed that copper plating had negative influence on the lifetime of galvanic layers in those conditions. Therefore, the use of sulfamate nickel as an intermediate layer was suggested. The coating with the sulfamate nickel layer was uniform with regard to geometric parameters over the whole surface analysed. Analysis of the distribution of elements within the layer area showed also the distinct interface between individual zones of the galvanic layer. The base layer is characterized by presence of phosphorus, while the outer layer by presence of chrome, which was presented in Fig. 5.