0

Full Content is available to subscribers

Subscribe/Learn More  >

Frictional Behavior of Boundary Lubricated Contacts: Effect of Tribochemical Surface Films

[+] Author Affiliations
C. Lorenzo-Martin, O. O. Ajayi

Argonne National Laboratory, Argonne, IL

JungKyu Lee, Andreas A. Polycarpou

University of Illinois at Urbana-Champaign, Urbana, IL

Paper No. IJTC2009-15098, pp. 79-81; 3 pages
doi:10.1115/IJTC2009-15098
From:
  • ASME/STLE 2009 International Joint Tribology Conference
  • ASME/STLE 2009 International Joint Tribology Conference
  • Memphis, Tennessee, USA, October 19–21, 2009
  • Conference Sponsors: Tribology Division
  • ISBN: 978-0-7918-4895-1 | eISBN: 978-0-7918-3862-4
  • Copyright © 2009 by ASME

abstract

The friction characteristics of lubricated contacts are usually determined by the shearing of three interfacial structural elements; namely lubricant fluid film, tribochemical reaction films and the near-surface materials. The shear behavior of the fluid film components of lubrication can be adequately described by either the hydrodynamic, or elastohydrodynamic theories and calculations. The shear behavior of the near surface materials can also be approximated by contact mechanics. However, due to the complexity and lack of adequate information, description and analysis of the tribochemical film contributions to frictional behavior is more challenging. In this study we present evaluation of the friction behavior of a lubricated contact as a function of tribological test duration, as the tribochemical surface films were being formed. Tests were conducted with two different formulated lubricants, in addition to an unformulated PAO basestock lubricant. One of the formulated lubricants consists of PAO synthetic basestock with 2.5% each of ZDDP and MoDTC additives. The other formulated lubricant is a fully formulated commercial gear oil with similar viscosity. During the friction tests in a fully flooded reciprocating sliding roller-on-flat contact configuration, the friction coefficient decreased exponentially as the tribochemical films were formed; highlighting the impact of boundary films on friction. In the test with the basestock fluid, the friction remained constant for the duration of the test; although an oxide layer was formed. Nanoindentation hardness and modulus measurements were conducted on two of the tribochemical films to measure their mechanical properties and the consequent impact on measured friction during testing.

Copyright © 2009 by ASME
Topics: Thin films

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In