**3. Electrochemical characteristics of corrosion resistance of metallic materials**

Metals are very commonly used materials in various technologies and applications. Properties of metallic materials are shaped by their composition and structure. Moreover, most natural metals are found in chemical combination with other elements. In the current study, resistance to electrochemical corrosion tests were applied to metallic materials with different properties and structures: aluminum (Al), aluminum with a surface layer of oxide aluminum (Al2O3), iron (Fe), S235JR steel, nickel (Ni), microcrystalline nickel (Nim), nanocrystalline nickel (Nin), and amorphous alloy of phosphorus-nickel (NiP). The choice of these materials was due to the universality of their applications in technology.
