12th Tooling Conference & Exhibition - Tooling 2022

Although anisotropic surface textures have been used to improve tribological performance in various mechanical systems in recent years, relatively few researchers have investigated the use of such textures in metal forming processes. In addition to achieving a better understanding of how anisotropic surfaces influence forming behaviour, it must also be considered that directional friction coefficients will also need to be developed for process modelling and analysis purposes. In the present study, experimental ring tests were used to calculate friction coefficients for H-13 platens which had an anisotropic texture (i.e. uni-directional grooves or surface lay). Friction factors were calculated parallel and perpendicular to the platen lay direction and then used to simulate hot compression of 6061-T6 Aluminium rings and bars using the DEFORM® system. The simulation results showed good agreement to experimental data and suggest that ring testing can be used as a means to establish numerical values for tool surfaces having directional grooves. The results also show that specimen orientation relative to the lay direction affected the degree of uniform flow and the resulting forming load. An example application based on strip rolling is also presented to illustrate the potential utility of anisotropic tool surfaces in hot working processes.