Desiccation of a clay film: Cracking versus peeling

TL;DR

This study uses a spring model to simulate the drying-induced cracking and peeling of a clay film, revealing how adhesion strength and drying rate influence the transition between these behaviors.

Contribution

It introduces a spring-based simulation approach to analyze the effects of drying and adhesion on clay film failure modes.

Findings

Phase diagram showing crack-peel transition based on adhesion and drying rate

Layer thickness affects crack number and width, matching experimental observations

Simulation reproduces experimental patterns of cracking and peeling

Abstract

Cracking and peeling of a layer of clay on desiccation has been simulated using a spring model. A vertical section through the layer with finite thickness is represented by a rectangular array of nodes connected by linear springs on a square lattice. The effect of reduction of the natural length of the springs, which mimics the drying is studied. Varying the strength of adhesion between sample and substrate and the rate of penetration of the drying front produces an interesting phase diagram, showing cross-over from peeling to cracking behavior. Changes in the number and width of cracks on varying the layer thickness is observed to reproduce experimental reports.