Experimental and numerical investigation of mechanical properties of PLA-based auxetic structures

Abstract In this study, two innovative unit cell designs were developed by combining different auxetic structures from the literature, and they were fabricated using 3D printers, one of the most popular additive manufacturing methods today. Tensile and compression samples were created based on unit cells produced with various parameters to investigate the mechanical properties of auxetic structures and their viability in the additive manufacturing field. Nowadays, polymer-based materials are widely accepted as the primary materials for 3D printing technology, which is employed in various engineering applications, including additive manufacturing. In this context, the samples were produced using PLA, subjected to tensile and compression tests, and their mechanical properties were analyzed. Additionally, finite element analysis (FEA) was utilized to simulate the tensile and compression tests in a virtual environment, and the results were compared with the experimental data. It was observed that the tensile and compressive strengths of the unit cell increased as the angle between the branches forming the unit cell decreased. Moreover, increasing the thickness of the branches that make up the unit cell also resulted in higher tensile and compressive strength values.