Influence of laser parameters in surface texturing of Ti6Al4V and AA2024-T3 alloys

Laser texturing can be used for surface modification of metallic alloys in order to improve their properties under service conditions. The generation of textures is determined by the relationship between the laser processing parameters and the physicochemical properties of the alloy to be modified. In the present work the basic mechanism of dimple generation is studied in two alloys of technological interest, titanium alloy Ti6Al4V and aluminium alloy AA2024-T3. Laser treatment was performed using a pulsed solid state Nd: Vanadate (Nd: YVO) laser with a pulse duration of 10 ps, operating at a wavelength of 1064 nm and 5 kHz repetition rate. Dimpled surface geometries were generated through ultrafast laser ablation while varying pulse energy between 1 µJ and 20 µJ/pulse and with pulse numbers from 10 to 200 pulses per spot. In addition, the generation of Laser Induced Periodic Surface Structures (LIPSS) nanostructures in both alloys, as well as the formation of random nanostructures in the impact zones are discussed.This work was supported by the Spanish Ministry of Science and Innovation [SMOTI MAT2009-13751] and the Spanish Ministry of Economy and Competitiveness [MAT2013-48224-C2-1-R-MUNSUTI]. Authors also acknowledge to Professor G. Dearden from the Laser Engineering Group, University of Liverpool, for his support for this study.Peer Reviewe