A parametric study of a pressurized blister test for an elastic-plastic film-rigid substrate system

A finite element simulation of a blister test of an elastic-plastic film, bonded to a substrate and subject to plane strain conditions, is performed. A traction-separation law models the fracture process ahead of the crack tip at the interface between the thin film and the substrate. Only two parameters are significant in describing the traction-separation law: adhesion energy, Γ0 and interface strength, σˆ. The dependences of the pressure, P, and the product of the pressure with the central deflection, PH, on the adhesion properties (Γ0 and σˆ), the geometry and material properties of the film are studied. The latter quantity (PH) has the same unit as the adhesion energy, Γ0, and is “conceptually” appropriate for the analysis. We suggest a method to extract the adhesion energy, Γ0 and the interface strength, σˆ, independently from the total energy dissipated.