Effect of Mn Content and Solution Annealing Temperature on the Corrosion Resistance of Stainless Steel Alloys

The corrosion behavior of two specially designed austenitic stainless steels (SSs) having different Nickel (Ni) and Manganese (Mn) contents was investigated. Prior to electrochemical tests, SS alloys were solution-annealed at two different temperatures, that is, at 1030°C for 2 h and 1050°C for 0.5 h. Potentiodynamic polarization (PD) tests were carried out in chloride and acidic chloride, whereas linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS) was performed in 0.5 M NaCl solution at room temperature. SEM/EDS investigations were carried out to study the microstructure and types of inclusions present in these alloys. Experimental results suggested that the alloy with highest Ni content and annealed at 1050°C/0.5 hr has the highest corrosion resistance.