Lubrication in fretting - a review

Lubrication is one of the important methods of preventing fretting damage owing to a remarkable reduction in the coefficient of friction. This review attempts to bring up-to-date the known facts concerning the lubrication in fretting situations. Results obtained by the authors in combination with results from literature are examined in detail. The effects of many lubricants on fretting behaviour have been investigated and some general features have been found although the majority of experimental data was obtained under quite differing conditions. In order to select successfully the right lubricant for a specific fretting application, representative lubricants, oil, grease, polymeric film and molybdenum disulphide (MoS2) with different physical states were used. Results indicate that the palliative effect on fretting should be analyzed using the fretting regimes concept. In particular, solid lubricant is most efficient in the partial slip regime while grease and oil, particularly the latter, are more suitable in the gross slip regime. Nevertheless, it has been noted that the lubrication mechanism in fretting is poorly understood and the need for further work is discussed. (C) 1999 Elsevier Science S.A. All rights reserved.