The influence of the process parameters of drag finishing on the surface topography of aluminium samples

Tribofinishing techniques are superfinishing processes that enable surface roughness improvement due to the mechanical action of abrasive media. A wide variety of kinematics can be employed and these abrasive media can have various trajectories and speeds when impacting the treated surface (normal, oblique, tangential, etc.). This work focuses on the drag finishing process, and in particular on the effect of spherical abrasive media impacting normally the surface of an aluminium part (6061T6). It investigates first the influence of the initial surface roughness and the diameter of spherical media when a lubricant is used. Secondly, it analyses the effect of a chemical accelerator surrounding abrasive media and the surface. An original experimental set-up was designed to observe the evolution of various surface roughness parameters and to identify local physical and chemical mechanisms. The results show that the final surface finishing greatly depends on the size of the abrasive media, and that a chemical additive can accelerate the material removal rate and improve the roughness when compared to a lubricant. (C) 2020 CIRP.