Investigating the Effect of Surface Finish on Mixed EHL in Rolling and Rolling-Sliding Contacts

Abstract

Surface finish may significantly affect the lubrication performance of a tribological interface through the influence of topography on micro/nanoscale fluid flows around localized contacts at surface asperities. This paper aims to study the mixed lubrication performance of a group of engineered surfaces, including turned, isotropically finished, ground, and dimpled surfaces, under different operation conditions by means of a deterministic mixed elastohydrodynamic lubrication (EHL) model. The honed surface was used to mate with other surfaces. The results indicate that a longitudinal contact ellipse favors longitudinally oriented mating surface roughness and that a transverse contact ellipse, as well as a line contact, prefers a transversely orientated mating surface roughness for lubrication enhancement.

KEY WORDS:

• EHL
• Micro-EHL
• Surface Roughness
• Film Thickness

ACKNOWLEDGEMENTS

The authors would like to thank the Timken Company for research support and permission to publish the results. Q. Wang and D. Zhu would like to acknowledge the support from the U.S. Department of Energy. Q. Wang is grateful for the support from U.S. National Science Foundation and Office of Naval Research.

Review led by Mike Khonsari