The effects of residual stress on fatigue behavior and crack propagation from laser shock processing-worked hole

Laser shock processing (LSP) is used to enhance the fatigue behavior of the structures. The effects of residual stress on fatigue behavior and crack propagation from LSP-worked hole were performed in this investigation. The influence of compressive stress on fatigue behavior and crack propagation of the hole was revealed, and a parametric study on residual stress and stress intensity factor was performed in order to determine their effect on crack growth propagation. The dislocation microstructure of 7050 aluminum at different laser intensities shows similar results, which indicated that LSP had an obvious inhibitory action to fatigue crack initiation and growth of the hole crack.

► Residual stresses and stress intensity factor changed in the LSP-worked zone. ► 7050-T7451 alloy hole crack initiation and growth are influenced by LSP. ► LSP has an inhibition effect on the material fatigue crack initiation and expansion.