Corrosion behavior of AISI 1045 carbon steel in simulated marine, acidic, and agricultural environments

This study investigates the corrosion behavior of AISI 1045 medium-carbon steel under three simulated corrosive environments: marine (NaCl), acidic (H 2 SO 4 ), and agricultural (NH 4 Cl). Tensile specimens were exposed for varying durations (1 and 5 days) and evaluated through corrosion rate measurements, surface hardness testing, tensile testing, and surface/fracture morphology analysis. The highest corrosion rate (7.41 mm·a −1 ) was recorded after 1 day of exposure to H 2 SO 4 which rapidly deteriorated mechanical properties due to aggressive acid attack and hydrogen-induced embrittlement. In contrast, NaCl exposure caused significant localized corrosion and a pronounced reduction in hardness (∼70 %), while NH 4 Cl exposure resulted in moderate and more uniform degradation. Tensile strength, elastic modulus, and ductility declined in all corroded specimens, correlating closely with fracture morphology and surface deterioration. These findings highlight the vulnerability of AISI 1045 steel to diverse environmental conditions and emphasize the need for protective strategies in service applications.