NUMERICAL AND EXPERIMENTAL INVESTIGATION OF THE EFFECT OF DELAMINATION DEFECT AT MATERIALS OF POLYETHYLENE TEREPHTHALATE (PET)PRODUCED BY ADDITIVE MANUFACTURING ON FLEXURAL RESISTANCE

Polyethylene terephthalate (PET) material, which is widely used in the packaging industry due to its thermal and mechanical properties, high chemical resistance, and low gas permeability, is among the most widely used polymer materials in the world. These properties have made their use in additive manufacturing methods widespread. Determining how some common additive manufacturing defects affect the products produced by these methods will increase the adoption of these technologies in the final product production. In this study, the investigation of the effect of layer non-joining defect called delamination on the impact strength of PET material produced by additive manufacturing method at different layer thicknesses was carried out experimentally and numerically. The effects to flexural stress on the artificially created layer adhesion defect on the middle layers of the parts produced and modeled with a layer thickness of 0.1/0.2/0.3mm were investigated. It has been observed that the increase in layer thickness decreases flexural strength. In addition, while the flexural strength of the specimens containing delamination decreased, the increase in layer thickness accelerated this decrease.