Mechanical Behavior and Energy Absorption of TPMS Diamond Structures and Hybrid SC-FCC-BCC Plate-Lattices

Architected cellular materials and structures provide the ability to tailor mechanical and functional properties based on design topological aspects. With the progressive advancement of additive manufacturing techniques, challenges and difficulties related to fabricating complex geometries are substantially reduced. Among different architected cellular materials, two types of closed-walls cellular materials, plate-lattices and triply periodic minimal surface (TPMS)-based lattices, provide outstanding mechanical properties. Plate-lattices are well-known for high stiffness, while TPMS lattices provide higher energy absorption capabilities. Herein, the mechanical behavior of the most two promising designs of both families is investigated experimentally and using finite-element analysis (FEA), namely sheet-based diamond TPMS and simple cubic-face-centered cubic-body-centered cubic (SC-FCC-BCC) plate-lattice. Fused deposition modeling (FDM) technology is utilized to fabricate the structures with acrylonitrile butadiene styrene (ABS) at several combinations of relative densities and unit cell sizes. Under quasi-static loading, diamond structures showed higher strength and energy absorption capabilities at various relative densities compared to plate-lattices. Based on experimental results, diamond is found to be 52% stiffer than the plate-lattice at low relative densities. These variations are diminished as relative density increased. ANOVA results, provided as main effects plots, show a significant dependence of mostly all mechanical properties on the three-dimensional (3D) topological design of the samples. Both structures presented outstanding mechanical energy absorption ability, suggesting their utilization in impact loading applications.