Elastohydrodynamic (EHD) lubrication is a lubrication regime characterized by the complete separation of contacting surfaces by a lubricant film. Friction in EHD contacts, caused by shear stresses within the lubricant film, is a critical factor affecting the performance and efficiency of thus lubricated mechanical systems. Experimental investigations were conducted using different concentrations of tetradecanoic and perfluorotetradecanoic acids as lubricant additives and their resulting frictional characteristics in EHD contacts were measured. Results of the tribological tests and further surface analyses have shown that perfluorocarboxylic acids demonstrate significantly superior friction reduction properties, even at low concentrations, compared to carboxylic acids, and have shown to be an effective novel strategy in reducing friction in EHD contacts.
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