Fachikova D.I.Ilieva G.P.Fachikov L.B.2024-07-162024-07-162024-07-162024-07-162022-01-011314-79781314-7471SCOPUS_ID:85128831689https://rlib.uctm.edu/handle/123456789/1368This communication addresses corrosion behaviors of two steels employed as construction elements in underground mining, precisely mild steel st.25 (0.23 % C) and low alloyed carbon steel KP-355 (0.19 % C, 0.96 % Cr, 0.36 % Cu). Tests were carried out in representative synthetic media containing chlorides and sulphates in different ratios and various pH. The concentration of the chloride and sulphate ions, as well the values of pH were relevant to the ranges of variations observed in real mining waters. The studies were performed by physical (optical microscopy) and electrochemical (potentiodynamic polarization) methods. The microstructures of both steels are almost identical, that is, they are ferrite-perlite in nature. The mechanical characteristics, the yield strength limit, Re, 0.2, MPa and tensile strength, Rm, MPa are higher to the alloyed steel respectively with about 30 % and 20 %. The polarization relationships allow obtaining the main parameters characterizing the corrosion process - the corrosion potential, Еcorr, V (SCE) and the corrosion current density, icorr, A сm-2. The latter are processed by the methods of mathematical statistics.enArticle