摘要:
The invention relates to a corrosion protection layer system for metal surfaces, said layer system comprising as the two top most layers: a) a discontinuous nickel-phosphorous layer and b) a chromium layer plated from a trivalent chromium electrolyte solution, as well as to a method of producing such a layer system. The inventive layer system is capable to combine the good corrosion resistance of the nickel-phosphorous layer against sodium chloride with the protective power of the chromium layer from the trivalent plating process against magnesium and calcium salts, especially without the need for any post-treatment.