%0 journal article
%@ 2051-3305
%A Sticchi, M.,Staron, P.,Sano, Y.,Meixer, M.,Klaus, M.,Rebelo-Kornmeier, J.,Huber, N.,Kashaev, N.

%D 2015
%J The Journal of Engineering
%N 13
%P 97-105 
%R doi:10.1049/joe.2015.0106
%T A parametric study of laser spot size and coverage on the laser shock peening induced residual stress in thin aluminium samples
%U https://doi.org/10.1049/joe.2015.0106
13 
%X Laser Shock Peening is a fatigue enhancement treatment using laser energy to induce compressive Residual Stresses (RS) in the outer layers of metallic components. This work describes the variations of introduced RS-field with peen size and coverage for thin metal samples treated with under-water-LSP. The specimens under investigation were of aluminium alloy AA2024-T351, AA2139-T3, AA7050-T76 and AA7075-T6, with thickness 1.9 mm. The RS were measured by using Hole Drilling with Electronic Speckle Pattern Interferometry and X-ray Diffraction. Of particular interest are the effects of the above mentioned parameters on the zero-depth value, which gives indication of the amount of RS through the thickness, and on the value of the surface compressive stresses, which indicates the magnitude of induced stresses. A 2D-axisymmetrical Finite Element model was created for a preliminary estimation of the stress field trend. From experimental results, correlated with numerical and analytical analysis, the following conclusions can be drawn: increasing the spot size the zero-depth value increases with no significant change of the maximum compressive stress; the increase of coverage leads to significant increase of the compressive stress; thin samples of Al-alloy with low Hugoniot Elastic Limit (HEL) reveal deeper compression field than alloy with higher HEL value.