Structure and Residual Stresses in the AMg6 Alloy after Laser Shock Processing

Abstract The microstructure and distribution of residual stresses in the AMg6 alloy after laser shock treatment in the power density range of 1.3–6 GW/cm2 have been studied. Using X-ray structural analysis, it has been found that, after laser exposure, the size of the coherent scattering regions (CSR) decreases to 60 nm, the value of microstrains increases to 0.0018, and the average dislocation density increases from 6.6 × 1013 to 3.7 × 1014 m–2. Laser shock treatment forms residual compressive stresses to a depth of 1 mm, reaching –128 MPa on the surface of the material.