Design and characterization of textured surfaces for metal forming applications

Surface texture has been the state-of-the-art in many tribological engineering applications to enhance lubrication as well as to improve wear resistivity. The present work focuses on textured surfaces manufactured by micro-milling and excimer laser texturing techniques on flat, hard tool steel surfaces. In order to promote lubrication entrapment and possible escape by micro-hydrodynamic lubrication mechanism, shallow, longitudinal grooves oriented perpendicular to sliding direction were designed and manufactured on the tool steel surfaces. The morphological characterization of the textured surfaces was performed using a tactile roughness profilometer, Light Optical Microscope (LOM), Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) measurements. It is found out that both surface texturing techniques are feasible for the surface texturing purposes. Assessment of resulting textured surface topographies by means of LOM, SEM and AFM analysis has revealed that the positive result regarding the desired textured surface profile by the excimer laser technique was obtained, owing to its ability to produce shallow groove depth and smaller groove angle than the micro-milled textured surface. This has been confirmed by observation on the laser textured surface topographies by using LOM, SEM and AFM measurements.