Jm. Baney et al., Experimental investigations of a stress intensity factor based descriptionof the adhesion of viscoelastic materials, LANGMUIR, 17(3), 2001, pp. 681-687
The relationship between the Tate at which cracks heal and the stress field
surrounding the crack tip has previously been suggested as a way to charac
terize the adhesive properties of viscoelastic systems. Crucial to this des
cription of adhesion is a predicted unique relationship between the crack h
ealing velocity and a stress intensity factor which completely characterize
s the stress field; it has been shown that this relationship should be inde
pendent of the applied loading history. We have experimentally investigated
this characterization of adhesion using JKR-type contact mechanics methods
. The experimental results indicate a dependence on the loading rate in the
relationship between the crack healing velocity and the stress intensity f
actor, contrary to the predictions of the theory. It is suggested that this
may be due to nonlinear material behavior near the crack tip, as the theor
y is based on linear viscoelasticity. More ideal systems may produce better
agreement between theory and experiment.