Transition from Cassie to Wenzel state in patterned soft elastomer sliding contacts

TL;DR

This study investigates the transition from Cassie to Wenzel states in patterned elastomer contacts, combining experimental and theoretical approaches to predict contact behavior under load.

Contribution

It introduces a coupled JKR and deformation model to accurately predict the load threshold for full contact in patterned elastomer contacts.

Findings

Transition occurs at a predictable load threshold.

Full contact area scales simply after onset.

The model aligns well with experimental data.

Abstract

In this paper, we presented an experimental and theoretical analysis of the formation of the contact between a smooth elastomer lens and an elastomer substrate micropatterned with hexagonal arrays of cylindrical pillars. We show using a JKR model coupled with a full description of the deformation of the substrate between the pillars that the transition between the top to the full contact is obtain when the normal load is increased above a well predicted threshold. We have also shown that above the onset of full contact, the evolution of the area of full contact was obeying a simple scaling.