A general expression for the maximum force in peeling a tape from a rigid substrate with an initial crack

Assuming a Dugdale cohesive zone, recently a simple Euler beam model has been proposed to understand the transient peeling on an elastic film from a rigid substrate at 90° from the substrate. The model also shows with sufficiently high bending stiffness, a peak force emerges larger than the Rivlin–Kendall steady-state value, scaling with the fourth root of bending stiffness. From the maximum force during peeling, and its steady-state value which is given by the Rivlin–Kendall well-known model, a simultaneous characterisation of the most important cohesive properties (cohesive strength and toughness of the interface) is obtained from a single test. This maximum force eventually saturates at a value which depends on cohesive strength alone. The presence of possibly inevitable initial cracks at the edge of the interface obviously reduces the peak force, and here, we give a simple closed-form approximate solution for this case too.