Laser Restoration of Sensitized Marine‐Grade Aluminum: Reclaiming Corrosion Resistance and Mechanical Integrity

This study proposes a novel laser desensitization method to address sensitization in 5083 aluminum alloy. The alloy is artificially sensitized via isothermal exposure at 150 °C for 21 days. Finite element simulations and nitric acid mass loss testing (NAMLT) are used to optimize the laser parameters. Intergranular corrosion testing, slow strain rate tensile testing (SSRT), NAMLT, electrochemical testing, and hardness testing are performed on laser‐desensitized and furnace‐desensitized samples. Laser desensitization at 240 °C with proportional‐integral‐derivative controlled power achieves the lowest NAMLT values. Electrochemical testing reveals a more positive corrosion potential, lower current density, and significantly higher impedance for the laser‐desensitized samples, indicating enhanced corrosion resistance. The SSRT results show that laser‐desensitized samples recover to presensitization levels in terms of tensile strength and elongation, and they exhibit 19.54% higher tensile strength and 43.14% higher elongation than furnace‐desensitized samples. Laser desensitization enables rapid processing within a few seconds, providing a significant advantage for time‐sensitive applications. These findings have demonstrated that laser desensitization is a highly effective and efficient technique for restoring corrosion resistance and preserving the mechanical properties of sensitized 5083 aluminum alloy.