Lubricant film formation in rough surface non-conformal conjunctions subjected to GPa pressures and high slide-to-roll ratios

Abstract A ball-on-disc machine was employed in a highly idealised setting to study the interplay between oil film formation and surface irregularities in single-sided rough elasto-hydrodynamic lubricated (EHL) conjunctions. The tests were operated under GPa pressures and high slide-to-roll ratios i...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Jonny Hansen, Marcus Björling, Roland Larsson
Formato:	article
Lenguaje:	EN
Publicado:	Nature Portfolio 2020
Materias:	Medicine R Science Q
Acceso en línea:	https://doaj.org/article/674c64d190d74c4d86a6df6858def023
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:674c64d190d74c4d86a6df6858def023
record_format	dspace
spelling	oai:doaj.org-article:674c64d190d74c4d86a6df6858def0232021-12-02T12:42:18ZLubricant film formation in rough surface non-conformal conjunctions subjected to GPa pressures and high slide-to-roll ratios10.1038/s41598-020-77434-y2045-2322https://doaj.org/article/674c64d190d74c4d86a6df6858def0232020-12-01T00:00:00Zhttps://doi.org/10.1038/s41598-020-77434-yhttps://doaj.org/toc/2045-2322Abstract A ball-on-disc machine was employed in a highly idealised setting to study the interplay between oil film formation and surface irregularities in single-sided rough elasto-hydrodynamic lubricated (EHL) conjunctions. The tests were operated under GPa pressures and high slide-to-roll ratios in a situation where the separating gap was smaller than the combined surface roughness height. Under the initial state of solid contact interference and with the operating conditions held fixed, surfaces were found to gradually conform such that a fully separating oil film of nanometre thickness eventually developed—a thin film lubrication state known as micro-EHL. Additionally, with a previously developed approach for 3D surface re-location analysis, we were able to very precisely specify the pertained nature of surface transformations, even at the asperity scale, by comparing the post-test surfaces to those in the virgin state. The surface roughness Sq was reduced by up to 17% after running-in, while the speed required for full film EHL was reduced by a remarkable 90%. Hence, full film EHL is possible even in cases where the Λ-ratio falsely suggests boundary lubrication. This discrepancy was attributed to the way surfaces are deformed inside the contact, i.e., through the establishment of micro-EHL.Jonny HansenMarcus BjörlingRoland LarssonNature PortfolioarticleMedicineRScienceQENScientific Reports, Vol 10, Iss 1, Pp 1-16 (2020)
institution	DOAJ
collection	DOAJ
language	EN
topic	Medicine R Science Q
spellingShingle	Medicine R Science Q Jonny Hansen Marcus Björling Roland Larsson Lubricant film formation in rough surface non-conformal conjunctions subjected to GPa pressures and high slide-to-roll ratios
description	Abstract A ball-on-disc machine was employed in a highly idealised setting to study the interplay between oil film formation and surface irregularities in single-sided rough elasto-hydrodynamic lubricated (EHL) conjunctions. The tests were operated under GPa pressures and high slide-to-roll ratios in a situation where the separating gap was smaller than the combined surface roughness height. Under the initial state of solid contact interference and with the operating conditions held fixed, surfaces were found to gradually conform such that a fully separating oil film of nanometre thickness eventually developed—a thin film lubrication state known as micro-EHL. Additionally, with a previously developed approach for 3D surface re-location analysis, we were able to very precisely specify the pertained nature of surface transformations, even at the asperity scale, by comparing the post-test surfaces to those in the virgin state. The surface roughness Sq was reduced by up to 17% after running-in, while the speed required for full film EHL was reduced by a remarkable 90%. Hence, full film EHL is possible even in cases where the Λ-ratio falsely suggests boundary lubrication. This discrepancy was attributed to the way surfaces are deformed inside the contact, i.e., through the establishment of micro-EHL.
format	article
author	Jonny Hansen Marcus Björling Roland Larsson
author_facet	Jonny Hansen Marcus Björling Roland Larsson
author_sort	Jonny Hansen
title	Lubricant film formation in rough surface non-conformal conjunctions subjected to GPa pressures and high slide-to-roll ratios
title_short	Lubricant film formation in rough surface non-conformal conjunctions subjected to GPa pressures and high slide-to-roll ratios
title_full	Lubricant film formation in rough surface non-conformal conjunctions subjected to GPa pressures and high slide-to-roll ratios
title_fullStr	Lubricant film formation in rough surface non-conformal conjunctions subjected to GPa pressures and high slide-to-roll ratios
title_full_unstemmed	Lubricant film formation in rough surface non-conformal conjunctions subjected to GPa pressures and high slide-to-roll ratios
title_sort	lubricant film formation in rough surface non-conformal conjunctions subjected to gpa pressures and high slide-to-roll ratios
publisher	Nature Portfolio
publishDate	2020
url	https://doaj.org/article/674c64d190d74c4d86a6df6858def023
work_keys_str_mv	AT jonnyhansen lubricantfilmformationinroughsurfacenonconformalconjunctionssubjectedtogpapressuresandhighslidetorollratios AT marcusbjorling lubricantfilmformationinroughsurfacenonconformalconjunctionssubjectedtogpapressuresandhighslidetorollratios AT rolandlarsson lubricantfilmformationinroughsurfacenonconformalconjunctionssubjectedtogpapressuresandhighslidetorollratios
_version_	1718393690450296832

Lubricant film formation in rough surface non-conformal conjunctions subjected to GPa pressures and high slide-to-roll ratios

Ejemplares similares