Laser-shock processing has now become a recognized surface treatment for generating compressive stresses in metallic materials, and improving surface properties such as fatigue, wear or corrosion properties. In our approach, finite element techniques have been applied to predict the residual stress fields induced in different materials (mainly stainless steels and aluminum alloys), combining shock wave hydrodynamics and strain rate dependent mechanical behavior. The predicted residual stress fields for single or multiple laser events were correlated satisfactorily with those from experimental data, with a specific focus on the influence of process parameters such as pressure pulse amplitude and duration, laser spot size or the specific influence of sacrificial overlay. This allowed us to re-visit all the influent parameters susceptible to modify residual stress fields induced by LSP. To improve simulations, the use of experimental VISAR determinations to determine (1) pressure loadings and (2) elastic limits under shock conditions (revealing different strain-rate sensitivities were found to be by a key-point). Also, a simplified thermo-mechanical model, taking into account the plasma heating contribution during LSP treatments without sacrificial overlay, was validated.
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