Correlation of elastohydrodynamic friction with molecular structure of highly refined hydrocarbon base oils
File(s)
Published version
Author(s)
Kim, Hak Mook
Spikes, Hugh
Type
Journal Article
Abstract
The molecular compositions of a range of low viscosity hydrocarbon base oils spanning API Groups II to IV have been quantified using 13C NMR and correlated with base oil elastohydrodynamic (EHD) friction. A strong correlation has been found between the proportions of paraffin, linear and branched carbons and EHD friction, with a high proportion of linear and paraffinic carbon atoms contributing to low-EHD friction but branched carbons contributing to high-EHD friction. Correlation equations have been developed to predict EHD friction based on base oil composition. At very high temperature and low pressure, this correlation breaks down as the lubricant in the contact does not reach sufficiently high shear stress for shear thinning to occur. For Group IV polyalphaolefin, the correlation must be extended to account for the very high proportion of linear carbons originating from linear alkene oligomerization. The correlations developed in this study can be used to guide the design of low-EHD friction base oils.
Date Issued
2020-03
Date Acceptance
2020-01-02
Citation
Tribology Letters, 2020, 68 (1), pp.1-14
ISSN
1023-8883
Publisher
Springer Science and Business Media LLC
Start Page
1
End Page
14
Journal / Book Title
Tribology Letters
Volume
68
Issue
1
Copyright Statement
© The Author(s) 2020. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Identifier
https://link.springer.com/article/10.1007%2Fs11249-020-1265-5
Grant Number
EP/P030211/1
Subjects
Mechanical Engineering & Transports
0912 Materials Engineering
0913 Mechanical Engineering
Publication Status
Published online
Article Number
23
Date Publish Online
2020-01-16