Application and development of laser shock peening for complex components

Laser shock peening (LSP) technology introduces controllable compressive residual stress (CRS) on the surface of the material through impact effect generated by laser beam, thereby significantly enhancing its mechanical properties. Firstly, the strengthening mechanism of LSP on material properties is discussed in detail, and the effects of surface curvature, laser energy and overlapping rate on residual stress (RS) are clarified. The influence weights that various parameters exert on different alloys vary. Then, the application of LSP in heteroideus components is reviewed. Among them, the high-cycle fatigue life of aviation blades can be increased by up to two orders of magnitude, the bending fatigue life of gears can be increased by nearly five times, and both the corrosion resistance of weld seams and the fatigue performance of small-hole components achieve remarkable results. Furthermore, an in-depth analysis is conducted on the technical difficulties existing in the applications of complex components, such as beam accessibility, deformation control of thin-walled parts, and the uniformity of strengthening for structures with sudden curvature changes. Finally, the key research directions and technical development trends in the future are enunciated, which should focus on intelligent process control, composite process optimization and special equipment development to cope with more complex engineering application requirements.