Assessing boundary film formation of lubricant additivised with 1-hexyl-3-methylimidazolium tetrafluoroborate using ECR as qualitative indicator

J L Viesca, A Hernández Battez, R González, T Reddyhoff, Angel Torres Pérez, H A Spikes

Research output: Contribution to JournalArticle

Abstract

Boundary film formation of ionic liquid (IL) 1-hexyl-3-methylimidazolium tetrafluoroborate, [HMIM][BF4], as an additive of hydrocracked mineral oil is evaluated for a steel–steel contact. Accelerated wear testing was carried out using a high frequency reciprocating rig (HFRR) under these test conditions: maximum contact pressure of 1.04 GPa, two different temperatures (40 and 100 °C) and three different times (300, 1800 and 3600 s). Wear volumes were measured using a non-contact 3D profilometer while worn surfaces were characterized using XPS. Furthermore, electrical contact resistance (ECR) was used as qualitative indicator of the formation of electrically insulating films in the sliding contact. Experiments show that the rate of boundary film formation of base oil-ionic liquid blend is faster than neat base oil. Moreover, ECR was in good agreement with film formation and friction behaviour. Ionic liquid as additive not only decreases the time of running-in but also the time of wear-in. Results of neat base oil show that wear-in was not reached during any duration of tests. The improved friction and wear results for the blend are closely related to the boundary film formation on the worn surfaces due to the reactivity of the anion with the steel surfaces.
Original languageEnglish
JournalWear
Volume269
Issue number1-2
DOIs
Publication statusPublished - 1 Jan 2010

Keywords

  • Ionic liquids
  • ECR
  • additive-deposited films
  • boundary lubrication wear
  • antiwear additives

Fingerprint Dive into the research topics of 'Assessing boundary film formation of lubricant additivised with 1-hexyl-3-methylimidazolium tetrafluoroborate using ECR as qualitative indicator'. Together they form a unique fingerprint.

  • Cite this