  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.
