Peeling behavior of a discontinuously adhered film/substrate system within finite deflection

In various fields such as biological adhesion, multi-chip semiconductors, ship hulls and hierarchical materials, adhesive layers often exhibit discontinuous characteristics. In this study, we develop a general model to explore the 90° peeling process of a film experiencing such discontinuous adhesion, employing the principle of minimum potential energy. The developed model is capable of handling arbitrary lengths of bonded and non-bonded segments and the large deformation of the film. In the process of film peeling under discontinuous adhesion, peeling force exhibits repetitive fluctuations. The peak signifies the initiation of the peeling front transitioning into the non-bonded segment, while the trough represents the delamination front advancing into the bonded segment. These fluctuations stem from the transfer and redistribution of bending energy in the film: energy release occurs as the peeling front enters the non-bonded segment, while re-accumulation takes place as it enters the bonded segment, resulting in increased peeling force. Additionally, we discuss the periodic discontinuous bonding, exploring different cases of bonding length proportions and period lengths. The conclusions drawn in this study are pertinent for accurately evaluating interface adhesion energy in multi-layered structures and comprehending the discontinuous adhesive interactions prevalent in nature.