Review on laser shock peening for Ni-based single-crystal superalloys: Microstructural evolution and performance enhancement

Ni-based single-crystal superalloys, as critical components in aerospace turbine engines, face severe challenges such as high-temperature oxidation, fatigue, wear, thermal corrosion, and creep deformation during extreme service. Laser shock peening (LSP) has emerged as a transformative surface modification technology, offering significant potential to enhance microstructural stability and mechanical performance. Although previous studies have investigated the application of LSP to Ni-based single-crystal superalloys in turbine blades, most studies are largely confined to verifying LSP's effect on individual performance metrics—such as high-temperature oxidation, thermal corrosion, or fatigue, without establishing how LSP-induced microstructural changes collectively affect overall performance. This review aims to examine the relationship between LSP-induced microstructural evolution (high-density dislocation networks, γ/γ′ phase redistribution, subgrain boundary formation, and compressive residual stress fields) and performance enhancement (high-temperature oxidation, corrosion resistance, tensile strength, thermal fatigue life) in Ni-based single-crystal superalloys. By integrating findings from multiple studies, this work provides a comprehensive assessment of LSP's potential to enhance thermal performance and extend the service life of Ni-based single-crystal superalloys in demanding environments, offering valuable insights for the development of next-generation high-performance turbine components.