Protective properties of zinc coatings on steel in neutral and acid media

Corrosion behavior of zinc-plated steel specimens in neutral salt fog and a cid fluid is studied. In the neutral medium, corrosion proceeds nonuniforml y according to the heterogeneity of chromate films; the zinc layer graduall y passivates and loses the properties of a protective anode. In this case, the protective properties of chromate film, which are ambigously dependent on both the plating and test conditions, become decisive. Economically and ecologically reasonable ways by which the protective ability of zinc coatin gs can be enhanced are proposed.