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Results are provided for corrosion tests of steel specimens with coatings of different compositions, prepared by surfacing under the action of a laser beam. Data are provided for weight loss of specimens coated with highly alloyed corrosion-resistant and tool steels, tin bronze, and alloys based on nickel and cobalt. The pH of working solutions is 3.1-9.0. the nature of corrosion damage and specimen transverse section structure are described. Research shows that use of protective coatings based on steel and on nonferrous metals may considerably reduce breakdown of objects manufactured from structural steels. The most marked reduction in weight loss due to corrosion develops for a coating based on cobalt (up to 82%). Alloys based on nickel and highly alloyed steels SS316L and SS410L showed an increase in corrosion resistance from 38 to 43%.Laser surfacing of materials is based on the capacity of a laser beam to create a high heat flux density in a small surface area. The high rate of laser surfacing compared with other surfacing methods, the significant thermal effect on an area around a joint as a result of a high heating rate, and metal heating and cooling rate, markedly reduce object metal participation in the surfacing layer.The quality and corrosion resistance properties of surfacing layer, prepared by laser surfacing, are determined to a considerable extent not only by the adhesive strength of a surfacing layer with a base, but also the degree of continuity of the surfacing metal through a layer thickness. Presence of porosity in surfacing metal with a significant difference in chemical composition of the main and deposited metals, markedly changes the corrosion resistance properties of a coating compared with the surface of a monolithic object, prepared from metal of similar chemical composition. In view of this, specimens have been studied with coatings of the following composition: highly alloyed corrosion-resistant steel; tool steel; bronze; metal coatings based on nickel and cobalt.Specimens were prepared by laser surfacing. The substrate was steel St. 3. The test media used were solutions prepared in distilled water. The general properties of solutions are presented in Table 1.Test coating corrosion resistance was evaluated according to weight loss in different media (test base 170 h, test temperature +25°C) showed that an acid medium with pH 3.1 exhibits the greatest dissolving activity. The least resistance for the

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