Enhanced corrosion resistance of aluminum alloys for marine environments via electromagnetic heating-assisted laser shock peening

Corrosion of aluminum alloys in marine environments critically limits the durability of ocean engineering structures. Conventional laser shock peening (LSP) can improve metal corrosion resistance through grain refinement but often struggle to maintain dense and stable surface microstructures. In this work, an electromagnetic heating-assisted laser shock peening (EH-LSP) is introduced to enhance the anti-corrosion performance of 5052 aluminum alloy. By heating the alloy to its dynamic strain aging (DSA) temperature (∼150°C) during the peening, thermal activation combines with high strain-rate deformation helps dislocation–solute interactions and keeps compressive stress stable. The EH-LSP produces a hardened layer of ∼1.2 mm, provides high surface quality and dense refined grains. The corrosion current density is reduced to 4.3 times lower than that of the untreated sample and 1.7 times lower than that of conventional LSP. It also demonstrates excellent corrosion protection in the simulated seawater corrosion tests. This work shows that the EH-LSP is an effective strategy for long-term corrosion protection of aluminum alloys in marine environments.