Laser shock processing of metal surfaces with cracks

Abstract

The article considers the application of the technology of laser shock processing surface treatment as a way to increase the fatigue properties of products. A numerical model based on the finite element method and analysis of the stress intensity factor is proposed, which makes it possible to assess the effect of treatment on crack propagation, as well as to determine the optimal technological modes. Studies were carried out that confirmed the adequacy of the proposed numerical model. The optimal technological modes of processing have been determined, which make it possible to create high compressive residual stresses that increase the crack resistance of the metal with a crack. It was found that for a linear crack, the treatment area should cover the maximum possible crack area; for a V-shaped crack, the treatment should be carried out at a distance of 2 mm from the crack tip to exclude the appearance of tensile residual stresses along the crack propagation path.