Localized high-temperature laser shock peening with adjustable metallic coatings method for mechanical properties enhancement of reflective aluminum alloys

The importance of temperature for the quality of laser shock peening has been recognized in recent years. Heat accumulation caused by the overall heating mode adopted by the existing method will inevitably cause changes in the microstructure of the unreinforced region, which in turn will affect the mechanical properties of the overall structure. In this paper, a localized high-temperature laser shock peening with adjustable metallic coatings (Loc-HLSPwC) was proposed for the low-cost, large-scale, and highly flexible fabrication of fatigue-enhanced structural components. The experimental results showed that compared with the samples fabricated by high-temperature laser shock without coatings, the strengthened regions of Loc-HLSPwC samples exhibited significant hardness and larger peak residual compressive stresses, and the Loc-HLSPwC samples exhibited more excellent fatigue performance. The adjustable metallic coatings changed the direction of microcrack expansion during the loading process of fatigue loading. The microstructure and hardness of the unstrengthened regions of Loc-HLSPwC samples did not change significantly. Loc-HLSPwC process is expected to provide a new idea for high reliability manufacturing of new generation of construction machinery equipment.