Impact of beam profile on surface texturing

Abstract

Several beam shaping strategies have been proposed as an effective approach to fully exploit the average power delivered by the last generation of high power, industrial, femtosecond laser whilst avoiding unwanted thermal effects. Nevertheless, in the case of surface texturing, the effect of the profile modifications on the surface morphology has been barely investigated. The objective of our study is to understand more deeply how the beam profile features will impact the surface evolution. By tailoring the beam profile, we want to understand if it is possible to increase the process throughput. A comprehensive study has been carried out with a 35 W, 2MHz, femtosecond industrial laser. The impact of the beam intensity profile on texturing of metallic surface has been investigated. We systematically studied how the beam size (from 10 μm to few hundreds of microns) impacts the generation and evolution of Laser Induced Periodic Surface Structures (LIPSS) on Stainless Steel surface. SEM analysis has been carried out for all the generated morphologies.