New efficient lubricant chemistries for the prevention of steel hydrogen embrittlement in modern drivetrains for low carbon transport

Drivetrains in electric and hydrogen-fuelled vehicles are shown to be susceptible to hydrogen release from the lubricant into bearings and gears. Insufficient reliability of these machine elements can be detrimental to energy efficiency and the rise of new low carbon technologies, seen as essential in achieving transport-related net zero carbon targets by 2050. Hydrogen release from lubricated contacts and its diffusion into steel is proven to lead to a premature material failure, limiting the reliability of bearings and gears. Through well-designed experimental and analytical research, the project will study the mechanisms of how hydrogen atoms are generated in sliding/rolling tribological interfaces and the role of surface-active lubricant additives in preventing hydrogen diffusion in steel. The experimental work will focus on tribological experiments using a test rig for in-situ monitoring of hydrogen evolution from tribochemical processes, accompanied by lubricant and surface characterisation. The ultimate goal is to propose and validate lubricant additive chemistries with customised tribological and hydrogen release performance. The project is supported by AC2T research GmbH (AC2T) located in Austria and the University of Leeds, and will involve a secondment in AC2T.

The project aims to utilise the Leeds-developed bespoke method for in-situ monitoring hydrogen evolution from tribological systems to study the relationship between lubricant composition and hydrogen release. Consequently, lubricant's ability to form dense and stable tribofilms will be exploited to prevent hydrogen diffusion into steel, improving drivetrains' reliability in low carbon transport systems.
Key objectives are:
- Quantify hydrogen diffusion into steel as a function of lubricant chemistry, tribological conditions and contamination.
- Utilise the tribofilm growth for preventing hydrogen evolution and diffusion.
- Apply the developed methods to formulate and validate new lubricant additives with customized tribological performance.