The paper explores the possibility of using a number of nickel alloys in multilayer coatings to decrease nickel consumption and preserve the functional effect of the coating. The following is proved by the graphical calculation technique using experimental data on the galvanic properties of the multilayer coating parts. Nickel-iron, nickel-phosphorus and nickel-tin alloy can be applied as a lower coating layer rather than semi-shiny, shiny or composite nickel. It is advisable to use a nickel-iron alloy as the middle (second) layer, and the concentration of iron depends on the composition of the first and third layers. If a nickel-iron alloy is applied as the material of the first layer, then the second layer may be semi-shiny (Ns-sh) or shiny (Nsh) nickel. The substitution of nickel layers for nickel alloys allows to considerably (about 10%) decrease the cost of a multilayer coating, while the protective properties are remaining the same. The application of the same nickel-containing alloys as single-layer anticorrosive coatings shows a lower level of protective properties.

One of the most effective means of protecting metalwork equipment premises from corrosion is currently zinc-plating. Zinc-plating increases the service life of the equipment by 2-3 times, i.e. up to 20 years, which makes this method economically justified.We measured the electrode potentials and corrosion current between two plates – steel and zinc, depending on the size of the zinc plate. Modeling of the corrosion process with a decrease in the zinc coating was carried out by reducing the area of the zinc plate. At the same time, the area of the steel plate was constant. The protective ability of the zinc coating is maintained as long as it occupies at least 10% of the surface area of the steel product. Reducing the area of the zinc coating leads to catastrophic corrosion failure of the coating.

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