Effect of surface wetting on tribological behavior for laser textured steel using ionic liquid-based lubricants

Abstract

In this study, the effect of surface wettability on the tribological performance is evaluated through a ball-on-flat reciprocating wear test. The substrate material, M2 tool steel, is laser processed and then functionalized with fluorocarbon and nitrile chemistry to achieve distinct oleophobicity and oleophilicity, respectively, but with a similar nanoscale surface texture. The poly-alpha-olefin (PAO) base oil is used as the baseline lubricant, and ammonium- and phosphonium-based oil-miscible ionic liquids (ILs) are used as additives. The interaction between the nanoscale textured steel surface and ionic liquid-based oils is investigated. A set of reciprocating wear tests are performed to identify the wear and frictional mechanisms of the tribosystem consisting of the surface-engineered, flat M2 tool steel specimen and a standard, surface-polished steel ball. Results show that the oleophobic flat surface results in a lower friction, while the oleophilic surface modification leads to a better wear protection to the flat surface. Ammonium-based IL provides the highest friction reduction, while the phosphonium-based IL provide an improved wear protection. Click here and insert your abstract text. © 2023 Society of Manufacturing Engineers (SME). Published by Elsevier Ltd. All rights reserved. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of the Scientific Committee of the NAMRI/SME. © 2023 The Author(s)