This study examines the passive film properties of Sn-5Sb alloy processed through Equal Channel Angular Pressing (ECAP) for application in gas turbine bearing pads. The alloy was analyzed in a 0.2 M Na2B4O7 solution utilizing multiple electrochemical methods, including cyclic voltammetry (CV), potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS). The microstructure and corrosion products were analyzed utilizing optical microscopy (OM), X-ray diffraction (XRD), and field emission scanning electron microscopy (FESEM). The findings indicated that ECAP processing enhanced the grain structure, leading to a protective layer with improved corrosion resistance. Positron Annihilation Lifetime Spectroscopy (PALS) and Coincidence Doppler Broadening Spectroscopy (CDBS) were utilized to identify corrosion-induced damage.

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