| AVS 56th International Symposium & Exhibition | |
| Tribology Focus Topic | Tuesday Sessions |
| Session TR+SS-TuA |
| Session: | Surface Science for Tribology |
| Presenter: | A. Erdemir, Argonne National Laboratory |
| Authors: | A. Erdemir, Argonne National Laboratory O. Eryilmaz, Argonne National Laboratory |
| Correspondent: | Click to Email |
Diamondlike carbon (DLC) films combine many attractive properties which make them good prospect for a wide range of engineering applications. Depending on the sources of carbon (i.e., hydrocarbon gases or solid carbon or graphite targets) and the type of deposition method, some of the DLC films may contain large amounts of hydrogen in their structures and they are relatively soft. Those that are produced from solid carbon and/or graphite targets by arc-PVD and pulsed laser deposition are nearly hydrogen free but very hard. However, regardless of their chemical and/or structural nature, all DLC films tend to be very sensitive toward the chemical composition of the test environments when tested for their friction and wear properties. In this study, we concentrate our attention on the friction and wear behaviors of both the hydrogenated and hydrogen-free DLC films in the presence of inert and reactive gaseous species like, argon, oxygen, hydrogen, and deuterium in test chambers. Using time-of-flight secondary electron mass spectrometry (TOF-SIMS), we explore the extent of tribochemical interactions that occurred during sliding tests. These studies have confirmed that the friction and wear behaviors of DLC films are indeed very closely controlled by the type and extent of tribochemical events that are triggered by the gaseous species in the surrounding atmosphere. In particular, hydrogen and deuterium in test environments seems to interact with the sliding surfaces of these films and thus have the greatest effect on friction and wear. Inert gases were detrimental for the friction and wear behaviors of hydrogen-free DLC, but beneficial to that of the highly hydrogenated DLC films. Based on the results from TOF-SIMS studies, we provide a mechanistic explanation for the tribochemistry of sliding surfaces and correlate these findings with the friction and wear behaviors of DLC films.