The Effect of Friction Modifiers in Rolling Contact: The Case of Oil-Lubricated Rolling Bearings

Modern rolling-element bearing lubricants contain a wide variety of additives to meet the ever-increasing demands of real-world applications. Nevertheless, scientific research focuses heavily on anti-wear additives and high-pressure additives. There are very few studies on the mechanism of action of various friction modifiers (FM) under rolling loads.
The importance of FM has increased significantly, as the desire to reduce friction and improve energy efficiency is at the heart of many developments. In the field of rolling bearings, however, excessively low friction between the rolling elements and the raceway can lead to increased slippage—that is, an increase in the sliding component during rolling. It is not yet known which friction behavior is advantageous for safe and low-wear operation: High friction to ensure a kinematically clean rolling process, or low friction to keep the energy input into the surfaces low and thus counteract damage. This issue plays a particularly significant role in highly dynamic acceleration and deceleration processes, where high inertial forces are at work. The number of such plants and systems is steadily increasing due to rising demands on production speed and drive dynamics.
The tribological laboratory testing methodology to be developed, in combination with optimized computer-aided rolling-element bearing calculations, will enable users to select the appropriate lubricant for a given application and ensure failure-free operation. This is applicable to all production and manufacturing sectors with a high proportion of SMEs. As a result, companies with limited resources in the areas of tribometry and simulation will be provided with a systematic approach that allows them to take friction behavior into account with sufficient accuracy when designing their bearing systems.

The grant notification from the BMWE has been received. The project will begin on November 1, 2026. The project is funded by the Federal Ministry for Economic Affairs and Energy pursuant to a resolution of the German Bundestag (IGF Project 01IF25613N).