Abstract
Hard coatings and surface adsorptive/reactive lubricants are two common strategies for improving wear protection, but what if they are used together? In this study, steel-steel and steel-coating sliding was investigated in boundary lubrication of polar and non-polar oils containing a ZDDP or an ionic liquid. Two hard coatings, diamond-like-carbon (DLC) and chromium nitride (CrN), were used. For a steel-steel contact, wear was effectively reduced by using a more surface reactive lubricant, as expected. However, the steel ball wear was increased against a hard coating and further worsened with a more polar oil and/or a more surface reactive additive. The wear mechanism is proposed as a combined effect of physicochemical interactions with the lubricant, mechanical polishing by the counterface, and material adhesion.
| Original language | English |
|---|---|
| Article number | 107010 |
| Journal | Tribology International |
| Volume | 160 |
| DOIs | |
| State | Published - Aug 2021 |
Funding
The authors thank M. Greaves from Dow Chemical for providing the PAG and OSP base oils. Research was supported by Vehicle Technologies Office, Office of Energy Efficiency and Renewable Energy, US Department of Energy (DOE). Electron microscopy characterization was performed at ORNL's Center for Nanophase Materials Sciences, sponsored by the Scientific User Facilities Division, Office of DOE-BES. This manuscript has been authored by UT-Battelle, LLC, under contract DE-AC05- 00OR22725 with the U.S. Department of Energy (DOE). The U.S. government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for U.S. government purposes. The U.S. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan Access Plan (http://energy.gov/downloads/doe-public-access-plan). This manuscript has been authored by UT-Battelle, LLC, under contract DE-AC05- 00OR22725 with the U.S. Department of Energy (DOE). The U.S. government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for U.S. government purposes. The U.S. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan Access Plan ( http://energy.gov/downloads/doe-public-access-plan ). The authors thank M. Greaves from Dow Chemical for providing the PAG and OSP base oils. Research was supported by Vehicle Technologies Office, Office of Energy Efficiency and Renewable Energy, US Department of Energy ( DOE ). Electron microscopy characterization was performed at ORNL’s Center for Nanophase Materials Sciences, sponsored by the Scientific User Facilities Division, Office of DOE-BES.
| Funders | Funder number |
|---|---|
| DOE Public Access Plan Access Plan | |
| Office of DOE-BES | DE-AC05- 00OR22725 |
| Scientific User Facilities Division | |
| U.S. Government | |
| U.S. Department of Energy | |
| Office of Energy Efficiency and Renewable Energy |
Keywords
- Chemical-mechanical polishing
- Chromium nitride (CrN) coating
- Diamond-like-carbon (DLC) coating
- Ionic liquid
- Oil additive
- PAG lubricant