Time Scales for Cold-Welding and the Origins of Stick-Slip Friction

TL;DR

This paper investigates the formation and rupture of nanometer-sized junctions between metal surfaces, revealing their role in the origins of stick-slip friction through long time-scale processes.

Contribution

It demonstrates that junction formation over ~60 seconds correlates with stick-slip dynamics, providing new insights into friction mechanisms.

Findings

Junctions form spontaneously over ~60 seconds.

Rupture parameters match stick-slip dynamics.

Junction formation influences macroscopic friction behavior.

Abstract

Data from an instrument that measures conductance, stiffness and rupture strength of junctions indicates that when two macroscopic metal surfaces are brought into contact a nanometer size junction spontaneously forms over a long time scale (~ 60 s). Furthermore, the parameters of junction rupture match the observed dynamics of stick-slip friction. This suggests that stick-slip friction has its origins in the formation and rupture of junctions that form between surfaces in contact.