Bioinspired 3D-Printed Auxetic Structures with Enhanced Fatigue Behavior

Recently, auxetic metastructures have gained considerable attention in various fields of study due to their unique characteristics. This study aims to design and fabricate bioinspired auxetic structures and comprehensively investigate the static and dynamic mechanical properties of those architectures under tensile and compressive loads. A comparative analysis is carried out with a conventional structure, considering static tensile and compressive tests, as well as dynamic tension-tension and compression-compression assessments. Experimental measurements and finite-element analysis are utilized to evaluate various parameters of the scaffolds, such as Young's modulus, yield strength, energy absorption, stress distribution, Poisson's ratio, and fatigue properties. The findings reveal that bioinspired auxetic structures can appropriately mimic the physical attributes and stress-strain characteristics of human tissue, such as the Achilles tendon. Furthermore, these bioinspired auxetic structures significantly enhance the cycles to failure compared to conventional structures, accompanied by notable improvements in energy absorption. Among the auxetic structures, the star configuration exhibits remarkable tolerance to tensile fatigue loads, while the sharp sinus structure demonstrates the highest tolerance to cycles to failure under compression-compression loads. The static and fatigue properties of bioinspired auxetic structures indicate their potential for biomedical applications. The world of auxetic structures, where innovation meets resilience, is dived into, unlocking the potential of auxetic metastructures and harnessing bioinspiration and fatigue resistance. Herein, how bioinspired designs mimic human tissue is explored, offering enhanced fatigue resistance and static mechanical properties. The future of materials engineering with auxetics-revolutionizing biomedical applications and beyond-is discovered.image (c) 2024 WILEY-VCH GmbH