Berlin 2015 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 31: Tribology

O 31.1: Vortrag

Dienstag, 17. März 2015, 14:00–14:15, MA 144

Influence of Temperature on Contact Ageing of Nano-Asperities — •Matthias Vorholzer, Dirk Dietzel, Michael Feldmann, and André Schirmeisen — Institute of Applied Physics, University of Giessen, Germany

In recent years research in nanotribology has advanced at an increasing pace. But although a lot of fundamental insight into various tribological processes has been gained, the problem of nanoscale contact ageing still remains largely unexplored. Recently, single-asperity slide-hold-slide experiments have been conducted with an AFM at room temperature under ambient conditions to directly investigate the evolution of static friction with time [1]. The results were explained based on a model that describes the formation of chemical bonds between the surfaces [2]. Thermal activation should thus play a major role in the temperature dependence of the ageing processes, which have been analyzed in this work under UHV conditions for temperatures ranging from 15K to 350K.

Our results confirm logarithmic increase of static friction over time for all temperatures. However, the distinct temperature dependence cannot be explained by purely thermally activated processes, which suggests that additional processes like viscoelastic contact area variations need to be considered.

[1] Li et al., Nature 480, 233-235 (2012) [2] Liu et al. PRL 109, 186102 (2012)