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Tribology Letters

, 67:73 | Cite as

Five-Stage Selection Procedure of Ionic Liquids for Lubrication of Steel–Steel Contacts in Space Mechanisms

  • Nicole DörrEmail author
  • Andreas Merstallinger
  • Roland Holzbauer
  • Vladimir Pejaković
  • Josef Brenner
  • Lucia Pisarova
  • Julia Stelzl
  • Marcella Frauscher
Original Paper
  • 103 Downloads

Abstract

An experimental approach using the stage-gate process is presented to efficiently select and assess ionic liquids (ILs) for their usability in space mechanisms, thus, for their potential to replace commonly used liquid lubricants based on perfluorinated polyethers and multiply alkylated cyclopentanes. This methodology was based on a five-stage selection procedure comprising the determination of rheological properties, outgassing properties, corrosion-inhibiting capabilities, screening of friction and wear performance in vacuum, which was completed by tribometrical lifetime assessments. Five ILs were benchmarked against Fomblin® Z25 as reference at the end of each stage and selected for the next stage depending on the performance. One IL of the type pyrrolidinium bis(trifluoromethylsulfonyl)amide outperformed Fomblin® Z25 in all stages except pour point. Thus, only in the case of fluidity at very low temperature showed Fomblin® Z25 a better performance. Additives slightly improved corrosion inhibition of this IL but showed adverse effects on friction and wear in comparison to the neat IL. In lifetime experiments, the IL resulted in a lifetime extension of at least factor 23 and 31 compared to the reference. Even with the use of additives in this IL, the lifetime extension was still by a factor of 6 to 15 compared to Fomblin® Z25.

Keywords

Space Ionic Liquids Fomblin® Z25 Thermal Stability Corrosion Vacuum Tribology 

Notes

Acknowledgements

The work presented was funded by the Austrian Space Applications Programme (ASAP project no. 840068) and carried out at the “Excellence Centre of Tribology” (AC2T research GmbH) and Aerospace & Advanced Composites GmbH. Parts of research project were also funded by the “Austrian COMET-Program” (project XTribology, no. 849109) via the Austrian Research Promotion Agency (FFG) and the Provinces of Niederösterreich, Vorarlberg, and Wien. The authors are grateful to Dr. Katharina Schröder from the Institute of Applied Synthetic Chemistry, TU Wien, for the chemical synthesis of IL5 and IL6. The authors also thank Nicholas Shore and Tobias Binder, all of AC2T research GmbH at the time of the study, and Dr. Christian Jogl of Aerospace & Advanced Composites GmbH for carrying out chemical syntheses and corrosion experiments, providing graphical material as well as performing SEM analyses.

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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.AC2T research GmbHWiener NeustadtAustria
  2. 2.Aerospace & Advanced Composites GmbHWiener NeustadtAustria

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