Experimental observation and finite element method modeling on scratch‐induced delamination of multilayer polymeric structures

Abstract

Scratches that result in delamination are common in multilayer polymeric laminates and coatings. In this study, the adhesive failure among a set of model double‐layer epoxy coatings was experimentally investigated and numerically analyzed using the finite element method modeling based on the maximum principal stress criterion. The adhesive failure on the model epoxy coatings was generated using an ASTM‐standard linearly increasing normal load scratch test. The parametric study reveals that delamination may initiate at locations underneath both scratch shoulder and behind scratch tip during scratching. It is also found that the magnitude and direction of peak tensile maximum principal stress developed at the interface are affected by both the laminate thickness and the material parameters of each layer. The parametric analysis shows that the onset of delamination can be delayed by possessing a softer base layer, a top or base layer with a higher yield stress, a base layer with a lower strain‐hardening slope, and a lower surface coefficient of friction. The Mode I delamination at the interface will become dominant in a multilayer system when the base layer has a higher modulus and a lower strain hardening slope. The usefulness of the present study for determining the delamination resistance of multilayer polymeric laminates and coatings is discussed.

Three-dimensional modelling of tensile behaviour for standard aluminium specimens

“…Mesh sensitivity analysis was done for model calibration using stress and deformation as the output parameters. After iterative element size optimisation, when less than 5 % change in the output parameters was observed irrespective of the element size, the meshing criteria were finalised for all specimens as shown in Table 4 [7,8,18,19]. Figure 3 represents the meshing and boundary conditions of the tensile specimen.…”

“…Finite element analysis (FEA) is an effective computational approach to solving various engineering problems by modelling a situation according to the applied boundary conditions and then obtaining a solution using different mathematical models. ANSYS is commercially available software that is frequently used to simulate such problems to obtain a numerical solution [7][8][9][10][11].…”

A green machining study to investigate the effect of nano-cutting fluid environments on the machinability of Ti6Al4V titanium alloy

“…60,61 Furthermore, because surface flaws can serve as the starting point for cracks, surface roughness plays a key role in determining how well any mechanical component performs. [62][63][64] Unfortunately, it is difficult and expensive to attain the necessary values for surface roughness, which makes roughness values for materials problematic. 65 The surface topography of the material changes on a microscopic scale when any test process is applied to the workpiece.…”

Experimental research on the non-uniform wear of the carbon strip of the metro pantograph

“…The material showed the formation of a multilayer oxide film, and the existence of the oxide film also played a role in lubrication, which reduced the friction coefficient. 28,29 The carbon strip had a certain self-lubricating property given that is a hightemperature metal-impregnated graphite material, such that the graphite particles showed a lubricating effect between friction pairs during sliding. [30][31][32] When the current and the relative sliding speed were constant, an increase in the normal contact force resulted in the bulge of the material being more prone to plastic deformation and brittle fracture, thus reducing the non-contact area and inhibiting the generation of the arc.…”