Buckling of a thin film strip in the microwedge indentation test

A one-dimensional delamination buckling model of a thin film was proposed for the microwedge indentation delamination test. The delamination buckling model is based on the Von Karman nonlinear plate theory and considers the substrate elastic deformation and the effect of the impression free-surfaces. The substrate deformation is modeled by employing three-coupled springs and the effect of the impression free-surfaces is modeled by using two-coupled springs. The critical stress is calculated. The results show that the critical stress is decreased by the substrate deformation and indentation induced notch. The critical stress depends greatly on the substrate deformation and the notch depth.