Influence of laser parameters on multiscale surface texturing of WC-Co: Formation, characterization and optimization

Abstract

This study explores the influence of laser parameters on the generation of multiscale topographies in Tungsten Carbide-10% Cobalt (WC-10% Co) in a single-step process. This material is frequently used in cutting tools for machining processes. Using a CB3-40 W solid-state pulsed laser with pulse durations ranging from 220 fs to 10 ps, experiments under non-protective atmosphere were conducted across a wide range of fluence values (0.2–16 J/cm²) and pulses per spot (3-200). The impact of different combinations of laser parameters on the formation of Laser-Induced Periodic Surface Structures (LIPSS) and micrometric textures was analyzed. Through various microscopy techniques like Scanning Electron Microscopy (SEM), Optical Microscopy Focus-Variation (OM F-V) and Atomic Force Microscopy (AFM), a multiscale characterization of the resultant surface features has been performed. The results reveal that higher pulse counts and peak fluences promote LIPSS formation, while shorter pulse durations enhance ablation depth. Furthermore, excessively aggressive laser parameters induced microcracks and defects, underscoring the importance of optimizing processing conditions.