Laser Peening Analysis of Aluminum 5083: A Finite Element Study

Abstract

In this research, a finite element (FE) technique was used to predict the residual stresses in laser-peened aluminum 5083 at different power densities. A dynamic pressure profile was used to create the pressure wave in an explicit model, and the stress results were extracted once the solution was stabilized. It is shown that as power density increases from 0.5 to 4 GW/cm2, the induced residual stresses develop monotonically deeper from 0.42 to 1.40 mm. However, with an increase in the power density, the maximum magnitude of the sub-surface stresses increases only up to a certain threshold (1 GW/cm2 for aluminum 5083). Above this threshold, a complex interaction of the elastic and plastic waves occurring at peak pressures above ≈2.5 Hugoniot Elastic Limit (HEL) results in decreased surface stresses. The FE results are corroborated with physical experiments and observations.

A Review of Laser Peening Methods for Single Crystal Ni-Based Superalloys

“…Typically, powder diffraction techniques such as sin 2 ψ or cos α are used for calculating stresses and strains via changes in interplanar spacings along specific planar axes in polycrystalline materials. In the case of the sin 2 ψ technique, diffraction data are collected at several angles of ψ, whereas the cos α technique makes use of an area detector that collects diffraction data (Debye-Scherrer ring) from a single X-ray beam, allowing for more expedient collection times [49][50][51]. While these techniques are used extensively for residual stress calculation of polycrystalline materials, they are rarely used for single crystalline materials due to additional experimental complexity associated with differences in diffraction behavior [45].…”