Influence of heat treatment on the mechanical and corrosion performance of 7050 aluminum alloy used in marine engineering

Purpose This study aims to investigate the effects of different heat treatment processes on the microstructure, mechanical properties and corrosion behavior of 7050 aluminum alloy. Design/methodology/approach The microstructure, hardness, mechanical properties, fracture morphology of 7050 aluminum alloy and their interrelations under various treatment conditions were systematically analyzed. Electrochemical tests (open-circuit potential and polarization curves) were used to study the influence of different heat treatment processes on the corrosion behavior of the aluminum alloy. Findings The 7050 aluminum alloy treated at 475 °C for 2 h followed by aging at 120 °C for 24 h exhibited the best mechanical properties. The corrosion tendency of 7050 aluminum alloy increased initially and then decreased as the aging time increased. The corrosion current density of samples aged for 0.5 and 2 h was higher, indicating poor corrosion resistance; the corrosion tendency reached its maximum at 24 h of aging, while the corrosion resistance significantly improved after aging for 48 and 72 h. Originality/value This study provides a theoretical basis and technical support for optimizing the heat treatment process of 7050 aluminum alloy and improving its corrosion resistance and reliability in practical applications.