Influences of microcontact shape on the state of a frictional interface

Abstract

The real area of contact of a frictional interface changes rapidly when the normal load is altered, and evolves slowly when normal load is held constant, aging over time. Traditionally, the total area of contact is considered a proxy for the frictional strength of the interface. Here we show that the state of a frictional interface is not entirely defined by the total real area of contact but depends on the geometrical nature of that contact as well. We directly visualize an interface between rough elastomers and smooth glass and identify that normal loading and frictional aging evolve the interface differently, even at a single contact level. We introduce a protocol wherein the real area of contact is held constant in time. Under these conditions, the interface is continually evolving; small contacts shrink and large contacts coarsen.

arXiv comment5 pages, 4 figures

References in corpus (4)

• Solid Friction from stick-slip to pinning and aging
• Rheological aging and rejuvenation in solid friction contacts
• Nonmonotonic Aging and Memory in a Frictional Interface
• Crack-Like Processes Governing the Onset of Frictional Slip

Cited by in corpus (5)

• Stochastic Properties of Static Friction
• Interfacial strength dominates fold formation in microscale, soft static friction
• Predicting frictional ageing from bulk relaxation measurements
• Beyond Quality and Quantity: Contact Distribution Encodes Frictional Strength
• Aging-Induced Dynamics for Statically Indeterminate System