Change search
ReferencesLink to record
Permanent link

Direct link
Wear in environmentally adapted lubricants with AW technology
KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.ORCID iD: 0000-0003-4447-3363
KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Tribologi.ORCID iD: 0000-0003-2489-0688
2008 (English)In: Journal of Synthetic Lubrication, ISSN 1557-6841, Vol. 25, no 4, 137-158 p.Article in journal (Refereed) Published
Abstract [en]

The purpose of the study was to examine the tribofilm formation and the corresponding wear occurring in the boundary lubrication regime in environmentally adapted lubricants, i.e. when using synthetic ester base fluids with different anti-wear additives. AW additives of the following types were studied: phosphorus, sulphur–phosphorus and sulphur–nitrogen together with an additive based on carbon, hydrogen, oxygen and nitrogen chemistry. In addition, the base fluid itself was tested.Wear was studied in a pin-on-disc-machine giving the wear coefficient. The surfaces were analysed by glow discharge-optical emission spectroscopy, revealing the surface reactions formed by the additives. The results indicate that the wear number decreases with increasing reacted surface layer depth as well as with increasing oxide layer depth. Also, the results indicate that a highly polar base fluid give relatively low wear numbers even without additives.

Place, publisher, year, edition, pages
2008. Vol. 25, no 4, 137-158 p.
Keyword [en]
tribology, environmentally adapted labricants, additives, surface analysis
National Category
URN: urn:nbn:se:kth:diva-78644DOI: 10.1002/jsl.57ScopusID: 2-s2.0-57149142254OAI: diva2:492729
QC 20120217Available from: 2012-02-08 Created: 2012-02-08 Last updated: 2012-09-25Bibliographically approved
In thesis
1. On tribological design in gear tooth contacts
Open this publication in new window or tab >>On tribological design in gear tooth contacts
2012 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The correct tribological design will have a considerable effect on a gear’s service life and efficiency. The purpose of this thesis is to clarify the impact of variation in the gear tooth flank tribological system on the gear contact load capacity – to increase the understanding of how surface topography and lubricant interact.

In this thesis the variation in surface topography inherent in the manufacturing method has been shown, by experimental work and computer simulations, to be an important factor for the contact condition in the early life of gears. Surface analysis revealed that the formation and composition of surface boundary layers depends strongly on the chemical composition of the lubricant, but also on pre-existing surface boundary layers. Additionally, surface boundary layers play a major role in frictional behaviour, wear and in allowing the lubricant to react properly with the surfaces.

Paper A presents the current ISO 6336 calculation of surface durability. A robust design approach was used to investigate the extent to which the current standard for calculation of surface durability allows for manufacturing variations and the choice of lubricant.

Paper B investigates the extent to which a logarithmical profile modification can increase gear contact pressure robustness compared to traditional lead profiles for gears.

Paper C compares different gear manufacturing methods and their as-manufactured (fresh unworn) surface topographies, using measured surface topographies as input to a contact simulation program.

Paper D examines surface boundary layer formation and the corresponding wear in relation to different anti-wear additives in an environmentally adapted base oil.

Papers E and F make use of specimens with surface topographies imitating two gear manufacturing methods (grinding and superfinishing) to be used in a twin-disc and barrel-on-disc machine respectively. The contacts are analysed by friction measurements and simulations combined with methods for surface analysis.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2012. 40 p.
Trita-MMK, ISSN 1400-1179 ; 2012:18
friction, gear contact, gear manufacturing, surface boundary layers, surface topography, wear
National Category
Mechanical Engineering Other Mechanical Engineering Tribology
urn:nbn:se:kth:diva-102742 (URN)978-91-7501-493-7 (ISBN)
Public defence
2012-10-15, Studion Gladan, Brinellvägen 85, KTH, Stockholm, 10:00 (English)

QC 20120925

Available from: 2012-09-25 Created: 2012-09-24 Last updated: 2012-09-25Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Bergseth, EllenOlofsson, Ulf
By organisation
Machine ElementsTribologi

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 89 hits
ReferencesLink to record
Permanent link

Direct link