The change in drive technology is resulting in new requirements for lubricants that have to meet the challenges of e-mobility. The development of future-oriented lubricant solutions is in full swing and new types of lubricants must be reliably evaluated, for example, with regard to their load-bearing behavior.
In electric motors in the drive train, significantly higher speeds are achieved than in internal combustion engines, which must be transmitted by the gears used. The use of a suitable gear lubricant ensures the tribological load-bearing capacity of the gear teeth in the transmission. Lubricants often contain performance additives whose effect is highly dependent on the operating conditions. Due to the complex physicochemical interactions between the lubricant components and the gear material, the performance of gear lubricants cannot yet be sufficiently estimated theoretically and must be verified and proven in lubricant tests.
Up to now, the evaluation of gear lubricants has been based on conventional operating conditions and is therefore carried out in the medium speed range. Initial experience with high speeds indicates a clear influence on the tooth flank load capacity. Suitable test methods are therefore required to reliably assess gear lubricants for e-mobility applications.