Vliv topografie třecích povrchů na utváření mazacího filmu za podmínek elastohydrodynamického a smíšeného mazání

Effects of surface topography on lubrication film formation within elastohydrodynamic and mixed lubricated non-conformal contacts

článek v časopise - ostatní, Jost

en

This paper focuses on the effects of surface topography modifications on lubrication film thickness within non-conformal lubricated contact. Optical test rig is used to study the lubricant film behavior between the flat surface of a chromium coated glass disc and a steel ball. An array of micro-dents was produced on the ball surface to be able to demonstrate the effect of surface topography on lubrication film formation. Experiments were carried out under elastohydrodynamic and mixed lubrication using steady state and transient operational conditions (start up and reversal motion). Obtained results have shown that surface texturing could represent the way how to increase lubrication efficiency of rolling/sliding non-conformal contacts under operational conditions when lubrication film is not able separate rubbing surfaces. Lubricant emitted from the micro-dent helps to reduce the asperities interaction. Moreover, the effect of surface micro-cavities has been observed within starved non-conformal contact under pure rolling conditions. An increase in film thickness within severe starved contact was localized upstream micro-dents that was recently predicted numerically. This effect was further amplified as lubricant released from micro-dent remains on the ball surface and again enters the contact after the ball turns round.

Článek je věnován vlivu topografie třecích povrchů na utváření mazacího filmu za podmínek elastohydrodynamického a smíšeného mazání.

This paper focuses on the effects of surface topography modifications on lubrication film thickness within non-conformal lubricated contact. Optical test rig is used to study the lubricant film behavior between the flat surface of a chromium coated glass disc and a steel ball. An array of micro-dents was produced on the ball surface to be able to demonstrate the effect of surface topography on lubrication film formation. Experiments were carried out under elastohydrodynamic and mixed lubrication using steady state and transient operational conditions (start up and reversal motion). Obtained results have shown that surface texturing could represent the way how to increase lubrication efficiency of rolling/sliding non-conformal contacts under operational conditions when lubrication film is not able separate rubbing surfaces. Lubricant emitted from the micro-dent helps to reduce the asperities interaction. Moreover, the effect of surface micro-cavities has been observed within starved non-conformal contact under pure rolling conditions. An increase in film thickness within severe starved contact was localized upstream micro-dents that was recently predicted numerically. This effect was further amplified as lubricant released from micro-dent remains on the ball surface and again enters the contact after the ball turns round.

Modifikace topografie; Elastohydrodynamické mazání; Smíšené mazání; Rozběh; Hladovění

Surface texturing; Elastohydrodynamic lubrication; Mixed lubrication; Start-up; Starvation; Reversal motion; Film thickness

2009

01.05.2009

Professional Engineering Publishing

Londýn

1350-6501

PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY

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1–9

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