Crack and pull-off dynamics of adhesive, viscoelastic solids

TL;DR

This study investigates how viscoelasticity affects the adhesion and detachment dynamics of elastomer contacts, revealing velocity-dependent adhesion maxima and mode transitions during pull-off.

Contribution

The paper presents simulations showing velocity-dependent adhesion behavior and mode transitions in viscoelastic solids during detachment, expanding understanding of dynamic fracture mechanics.

Findings

Maximum adhesion occurs at intermediate pull-off velocities.

Tensile forces increase monotonically with pull-off speed.

Fracture mode shifts from crack propagation to uniform bond breaking.

Abstract

When quickly detaching an elastomer from a counterface, viscoelasticity dramatically increases the perceived adhesion relative to its adiabatic or equilibrium value. Here, we report simulations on the sticking contact between a rigid cylinder and a viscoelastic half space revealing a maximum in the work of adhesion at intermediate pull-off velocities. Maximum tensile forces yet increase monotonically with the pull-off speed and the crack-tip speed in accordance with the Persson-Brener approach. As predicted theoretically, the fracture mode transitions from interfacial crack propagation to quasi-uniform bond breaking with increasing range of adhesion.