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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.more » « less
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null (Ed.)Various mechanical systems are subjected to inherent oscillatory motions often paired with extreme, high-temperature environments resulting in fretting wear. In this work, the fretting wear resistance of additively manufactured Inconel 625 was studied at room and elevated temperatures. In-situ temperature-controlled nanoindentation was employed to further elucidate mechanical property evolution as a function of temperature. The results showed a 30% decrease in near-surface mean hardness at 510 °C compared to room temperature. However, the material exhibited significantly lower wear and coefficient of friction values at high temperatures, attributed to the formation of a compacted, intermediate oxide layer preventing excessive friction and wear.more » « less
