Experimental assessment of the influence of irradiation parameters on surface deformation and residual stresses in laser shock processed metallic alloys

Laser shock processing (LSP) has been proposed as a competitive alternative technology to classical surface treatments for improving fatigue, corrosion and wear resistance of metals, and has recently been developed as a practical process amenable to production engineering. In the present paper a summary is provided of different experimental results obtained from the most recent LSP experiments carried out by the authors along with some conclusions for the assessment of LSP technology as a profitable method for the extension of fatigue life in critical heavy duty components. In particular, a principle demonstration has been obtained on the capability of frequency doubled Nd:YAG lasers to induce compressive residual stresses in a highly deformable material as aluminium, although reasonable doubts arise on their capability to induce these tensions over extended depths (what is really an objective in comparison with other competitive technologies) or in less deformable materials (i.e. stainless steels). (C) 2004 Elsevier B.V. All rights reserved.