Non-local orthotropic damage-plastic model for 3D printed materials

A non-local orthotropic damage and plasticity phenomenological model for 3D printed materials is presented. The model specifically refers to 3D printed structural elements realized with an extrusion-based technique and made with thermoplastic materials. The structural behavior of the 3D printed component is described with a laminate finite element model based on the first-order shear deformation theory. Each layer of the laminate is described with a non-local orthotropic damage and plastic model. Indeed, the overall mechanical response of 3D printed materials is significantly influenced by plasticity and damage mechanisms that can lead to a range of failure modes from brittle-like to ductile. The proposed orthotropic damage model is based on the introduction of three different damage parameters. Each of them describes a specific damage mechanism, i.e. fiber breakage, fiber detachment and delamination, that is clearly visible from the analysis of the 3D printed samples subjected to experimental tests. Some applications are carried out and the numerical results are compared with experimental results available in literature, highlighting the effectiveness of the proposed modeling technique.