Analysis of 3D Printed Trapezoidal Interfaces by Means of a Novel Cohesive-Based Analytical Approach

The advances in manufacturing techniques allow the generation of new geometric conceptions and open a new paradigm in adhesive joints design. Structured interfaces constitute an excellent method to improve the resistance properties of these kinds of joining systems, Additive Layer Manufacturing (ALM or 3D printing) being an appropriate procedure to perform these designs. In this study, double-cantilever beam (DCB) tests with different trapezoidal patterns are investigated in terms of fracture resistance from experimental and analytical points of view in order to analyze the influence of the geometry in the energy release rate of the structure. The main goal of the current investigation is to examine the system response under the variation of the analytical approach parameters (based on a cohesive-zone model (CZM) technique). Particularly, a wider range of mixed-mode fracture conditions can be integrated by means of establishing different penalty stiffnesses in normal and shear directions, [Formula: see text] and [Formula: see text], respectively. Finally, a correlation between the experimental and analytical results for the proposed trapezoidal interfaces with different aspect ratios [Formula: see text] (where [Formula: see text] and [Formula: see text] identify the amplitude and wavelength of the interface profile, respectively) is shown. A satisfactory agreement between the predicted and the experimental data is achieved, emphasizing that the relation [Formula: see text] has a significant influence on the results obtained and, therefore, a correct characterization of the joint is needed.