How Does Adhesion Induce the Formation of Telephone Cord Buckles?

Abstract

Compressively stressed thin films with low adhesion frequently buckle and delaminate simultaneously into telephone cords. Although these buckles have been studied for decades, no complete understanding of their propagation has so far been presented. In this study, we have coupled a nonlinear plate deformation with a cohesive zone model to simulate the kinematics of a propagating telephone cord buckle in very close agreement with experimental observations. Proper inclusion of the dependence of an adhesion upon the mode mixity proved to be central to the success of the approach. The clarification of the mechanism promises better understanding of buckle morphologies.

Ultra-thin nanocrystalline diamond membranes as pressure sensors for harsh environments

“…16 This could be induced by the growth conditions 17 and by the mismatch between the thermal expansion coefficients of glass and diamond. Etch depths were measured as a function of etch time with a micrometer height gauge and then fitted with d ¼ c ffi ffi t p .…”

The effect of interface adhesion on buckling and cracking of hard thin films

“…14,16 It has been shown that by taking into account interface adhesion using a cohesive zone model, the kinematics of a propagating telephone cord buckle can be simulated. 17 It has also been demonstrated that the height and width of the buckles are related to the properties of the cohesive zone in both FEM simulations 18,19 and atomistic simulations. 16,20 Scanning electron microscopy (SEM) images of a Ti 0.39 Si 0.04 N 0.57 thin film grown on a silicon substrate using DC reactive magnetron sputtering 4 showed that various buckling patterns were generated including circular blisters, straight-sided wrinkles and telephone cords with widths or diameters in the range of 15-25 µm.…”

“…A value of λ 0.14 was used in the simulations based on the range of reported values (0.05-0.25). 17,27 We assumed 0.02 0.07 , 17 10 , 17 and 2 , 28 with and being the normal and shear stiffness of the interface, respectively, and the experimentally reported residual stress. 4 To trigger the buckling, the film is perturbed in the out-of-plane direction with a small imperfection.…”

Strength Analysis of Anisotropic Thermal Barrier Coating under Heat Shock

“…Similar approaches are described in the literature [6,7]. In the course of delamination the coating can take the corrugation form, and the period of the formed structure is a function of foundation and coating adhesion [8]. The following analysis stages are presented:…”