Development and application of a test rig for tribological investigations under impact loads

The investigation and the understanding of frictional mechanisms occurring between forming dies and work pieces in tribological contact is the prerequisite for the development of novel, dry bulk metal forming processes such as dry rotary swaging. The capability to conduct tribological investigations within the actual forming processes, however, is strongly limited, e.g. due to the limited accessibility of force measurement equipment. This work presents the development and application of a tribological test rig mimicking typical contact geometries and high impact loads associated with infeed rotary swaging for process-independent tribological investigations. The development comprises the designing process based on rotary swaging process simulations, setup assembly, and calibration procedure. Subsequently, the functionality of the test rig was demonstrated successfully, determining the distinct frictional properties under lubricated and dry conditions of various samples with structured surfaces representative for rotary swaging dies.