| AVS 62nd International Symposium & Exhibition | |
| Tribology Focus Topic | Thursday Sessions |
| Session TR+AS+NS+SS-ThA |
| Session: | Molecular Origins of Friction |
| Presenter: | Erin Flater, Luther College |
| Authors: | E. Flater, Luther College S. Sorenson, Luther College N. Ansari, Auburn University A. Poda, Auburn University W.R. Ashurst, Auburn University B.P. Borovsky, St. Olaf College |
| Correspondent: | Click to Email |
Understanding of tribological mechanisms at the submillimeter scale continues to be relevant since friction and wear limit the commercial viability of small-scale mechanical devices such as microelectromechanical systems (MEMS). For example, tribochemical processes play a significant role in many materials systems, including silicon oxide and aluminum oxide, which are relevant materials for MEMS devices. Our work focuses on understanding tribological processes at the interface of silicon AFM tips and amorphous aluminum oxide surfaces. We observe wear of silicon tips after repetitive sliding on the aluminum oxide surface, which occurs even at low contact pressures, implying that the wear process is chemical in nature. We quantify tip wear by intermittently interrupting the wear experiment to perform indirect in-situ tip imaging on a sharp-spiked sample. We use these tip images to quantify volume of material lost during scanning. Wear as a function of sliding distance is modeled using reaction rate theory and is compared to the Archard wear model. While some of our results appear to agree with an Archard model, these results may be more appropriately interpreted in light of the more fundamental reaction rate theory.