Revisiting liquid lubrication methods by means of a fully coupled approach combining plastic deformation and liquid lubrication

This paper presents a new approach based on a fully coupled procedure in which the lubricant flow and the plasticdeformation of the metallic material in metal forming are solved simultaneously. The proposed method is an alternativeto conventional modelling techniques which allow studying the effect of a broad range of parameters directly on thefriction conditions. The approach is applied to strip reduction of a sheet with mesoscopic surface pockets in order toinvestigate the escape of lubricant from the pocket by means of Micro Plasto HydroDynamic Lubrication and MicroPlasto HydroStatic Lubrication. For the investigation on Micro Plasto HydroStatic Lubrication, the friction along thetool–workpiece contact interface and the back tension are taken as parameters, and the backward escape Micro PlastoHydroDynamic Lubrication is investigated by variations in lubricant viscosity by means of a combined numerical andanalytical model, and by variations in drawing speed. Good agreement is found with the experimental observations.