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Laser Shock Processing (LSP) has been demonstrated as an effective technology for improving surface and mechanical properties of metals. The main recognized advantages of the technique consist in its capability of inducing a relatively deep compression residual stresses field allowing an improved mechanical behaviour against fatigue crack initiation and growth, mechanical wear and stress corrosion. Although significant experimental work has been performed in order to explore the optimum conditions for the application of the treatments and to assess their capability to provide enhanced mechanical properties, only limited attempts have been developed in the way of physical understanding of the characteristic processes and transformations taking place under the LSP regime. In the present paper, the integrated numerical-experimental approach to LSP processes design developed by the authors is presented, the incorporation of increasingly more accurate models for the characterization of metallic materials behaviour under LSP conditions being an always present objective. Different practical results at laboratory scale on the application of the LSP technique to different materials with different irradiation parameters are presented along with physical interpretations of the induced mechanical effects. Concrete issues as laser-plasma interaction in the ns, GW/cm2 regime, material behaviour description for cyclically compressed matter, numerical simulation methods for the coupled plasma-thermomechanic analysis, practical implementation of the technique according to different approaches, etc. are discussed in the view of the last developments contributed by the authors and, finally, a tentative summary of the still open questions for the better knowledge and control of the process is presented.
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