The electrochemistry of the corrosion products formed from carbon and weathering steel during four years of atmospheric exposure were investigated using a carbon paste electrode (CPE) by cyclic and square wave voltammetry. The iron rust products with crystalline nature were identified from their standard formal potential. The corrosion protection ability of the rust layers were determined by polarization and electrochemical impedance spectroscopy studies using CPE. ATR‐FTIR, SEM and XRD studies were employed to identify the composition and morphology of the corrosion products which supports SWV results. Results showed that the weathering steel has higher corrosion resistance than the carbon steel.