Paper TR3+NS-ThA7
A Scanning Tunneling Microscope and Quartz Crystal Microbalance Study of Heating and Wear at a Sliding Interface

Thursday, October 18, 2007, 4:00 pm, Room 617

In order to probe the rise in temperature of a sliding interface, a Scanning Tunneling Microscope and Quartz Crystal Microbalance has been combined to produce a rubbing action of a tungsten tip on a copper and indium electrode, respectively. The amplitude of oscillation¹ and wear of the electrodes is observed directly with the STM. Negative frequency shifts, which are indicative of a liquid-solid interface,² were observed for tungsten on indium rubbing. The chamber was heated and negative frequencies were observed at reduced sliding speeds, implying surface melting at the indium interface. This work was funded by The National Science Foundation and the AFOSR Extreme Friction MURI.

¹B. Borovsky, B. L. Mason, and J. Krim, J. Appl. Phys. 88, 4017 (2000).
²C. M. Flanigan, M Desai, and K. R. Shull, Langmuir. 16, 9825 (2000).