Theoretical study of mechanical behavior of thin circular film adhered to a flat punch

In this paper we present a theoretical study of the cylindrical punch test where a thin circular film clamped at the periphery is adhered to the planar surface of a rigid cylindrical punch, and an external tensile load is applied to the punch causing the film to delaminate from the substrate. We obtain analytical solutions to the deflection of the membrane in the asymptotic limit of large or small loads, and then combine the bending and stretching effects using a lumped parameter force-deflection model. An equilibrium theory of delamination mechanics is derived based on energy balance. The cases of initially stress-free and prestressed film are analyzed, which ought to have significant implications in many technological situations.