Surface treatment of aluminium alloy by laser shock processing

Abstract

Laser shock processing is a novel surface treatment, distinct from shot peening, explosive treatment, and high power continuous laser treatment, for improving the fatigue resistance of metals. The effects of laser shock treatment on the fatigue life of 2024–T62 aluminium alloy have been studied. The fatigue test results show that the average life of laser shock treated specimens is six times that of unshocked ones. The fatigue life improvement is attributed to the combined effects of reduced surface roughness, increased dislocation density, and compressive surface residual stress.