Results of friction benchmark in cold forging condition
Résumé
The paper presents the results of a benchmark on friction data evaluation in cold forging conditions. The benchmark was carried out in the framework of the European project VIF-CA "Virtual Intelligent Forging" with the participation of five research laboratories. In this work, an AISI 1010 low carbon steel bar with phosphate and soap coating was chosen as the reference material. A real industrial extrusion was chosen as reference process to obtain the process conditions under which friction has to be evaluated. Different friction tests, including forward extrusion, double-cup extrusion, upsetting-sliding test and T-shape compression, were set-up and carried out to evaluate the friction conditions. According to friction factors and friction stresses obtained through these tests, the contact pressure and surface expansion ratio have significant effects on friction. Therefore, in order to choose a suitable friction test for a given forging operation, the contact pressure and surface expansion ratio of the chosen friction test and the ones of the analysed industrial operation should be as similar as possible.