Experimentální studium reálných povrchových nerovností v EHD bodových kontaktech

Experimental Study of Real Roughness Features within EHD Point Contacts

conference paper

en

A combination of thin film colorimetric interferometry and phase shifting interferometry has been used to study the effect of slide-to-roll ratio on the micro-elastohydrodynamic action and asperity-contact mechanism on the real asperity scale. The phase shifting interferometry was used to measure in-situ initial undeformed rough surface profiles and thin film colorimetric interferometry provided accurate information about micro-EHD film thickness behaviour over a wide range of operating conditions. Lubricant film thickness distribution within mixed EHD contact has been found to change significantly as a function of a slide-roll ratio. A high resolution color camera has enabled a closer look at film thickness changes in the vicinity of surface irregularities that helped to describe these processes in detail. Obtained results indicate the presence of either a boundary film less than 1 nm thick or some solid-like contact in front of roughness features for positive slide to roll ratios. No such a local film thickness reduction has been found for negative slide-to-roll ratio conditions.

Kombinace kolorimetrické interferometrie a interferometrie s řízenou změnou fáze byla použita při studiu vlivu povrchových nerovností na utváření mazacího filmu. Pro pozorování přechodových jevů byl použit xenonový záblekový zdroj, který umožnil snímání interferenčních obrazců při průchodu nerovností mazaným kontaktem. Byl ukázán vliv provozních podmínek na změny v mazacím filmu.

A combination of thin film colorimetric interferometry and phase shifting interferometry has been used to study the effect of slide-to-roll ratio on the micro-elastohydrodynamic action and asperity-contact mechanism on the real asperity scale. The phase shifting interferometry was used to measure in-situ initial undeformed rough surface profiles and thin film colorimetric interferometry provided accurate information about micro-EHD film thickness behaviour over a wide range of operating conditions. Lubricant film thickness distribution within mixed EHD contact has been found to change significantly as a function of a slide-roll ratio. A high resolution color camera has enabled a closer look at film thickness changes in the vicinity of surface irregularities that helped to describe these processes in detail. Obtained results indicate the presence of either a boundary film less than 1 nm thick or some solid-like contact in front of roughness features for positive slide to roll ratios. No such a local film thickness reduction has been found for negative slide-to-roll ratio conditions.

film thickness, colorimetric interferometry, mixed lubrication

2005

01.10.2005

ASME

Washington, USA

Proceedings of the 3rd World Tribology Congress

2