Service behaviour of PVD-coated gearings and bearings lubricated with biodegradable oils

The following report presents the results of practical investigations with PVD coated gears and spindle bearings in combination with biodegradable lubricants. In order to compensate the performance deficit and the rising wear of the mechanical components when using non-additived oils, suitable PVD coating systems were used on the loaded surfaces. This coatings are capable of substituting the tribological functions of conventional, additivated lubricants. All investigations have been carried out in the context of the Collaborative Research Center 442 ("environmentally friendly tribosystems by suitable coatings and fluids with respect to the machine tool"). The aim is to realize an environment-friendly system consisting of the mechanical components and the corresponding lubricants, which at least provides an equal performance compared to conventional systems.