| Abstract Scope |
This study presents auxetic-based solid-lattice hybrid structures for lightweight components with high energy-absorption capabilities. A hexagonal auxetic structure and six modified variants were evaluated by varying key geometric parameters, including member length (5 - 9 mm), orientation angle (50 - 70 °), and extrusion thickness (0.4 - 0.8 mm), using a design of experiments approach. The Johnson-Cook plasticity model was adopted to predict the effective modulus, strain energy absorption and stress distribution over the lattice structure under prescribed loading conditions. A Gaussian process regression model combined with NSGA-II enabled multi-objective optimization to minimize mass while maximizing stiffness and energy absorption. The optimal design, with parametric values of length: 5.012 mm, angle: 60.25 °, and thickness: 0.4002 mm, resulted in a ~43% weight reduction and enhanced energy absorption. Finally, the optimized auxetic lattice was integrated into a topologically optimized structure forming a solid-lattice hybrid design for additive manufacturing. |