The paper explores enhancing the mechanical behavior of stochastic lattice structures through a semi-controlled design approach. By leveraging the Gibson-Ashby model and predefined geometric routines, the study aims to optimize the mechanical response of lattice structures under compressive stress. Transitioning from stochastic to semi-controlled tessellation using Rhinoceros 7 software enables more predictable deformation behavior. Design parameters such as node formation, strut thickness, and lattice generation patterns are correlated with relative density to regulate stiffness and strength. Experimental validation using Acrylic Styrene Acrylonitrile (ASA) filament demonstrates the effectiveness of the proposed design model. The research emphasizes the importance of understanding internal mechanics by introducing a novel design approach to control geometry and topology arrangement in shaping lattice properties. By introducing a semi-controlled mechanism, the study seeks to improve the reliability and uniformity of mechanical responses in lattice structures. The findings highlighted the benefits of semi-controlled design approaches in achieving tailored mechanical properties. Specimens were compression tested in quasi-static uniaxial loading and showed that structures created with parabolic distribution dimensioned by ${\mathrm{h}}_{\mathrm{p}}=0.5{\mathrm{h}}_{\mathrm{v}}$ originated the most reliable and most vital mechanical response compared with other design models, including typical Voronoi distribution. The improved mechanical response in between proposed design models constantly progressed by about 15% on average consecutively, starting from the parabolic distribution dimensioned by ${\mathrm{h}}_{\mathrm{p}}=1.0{\mathrm{h}}_{\mathrm{v}}$ as the weakest ranked, up to the best one, dimensioned by ${\mathrm{h}}_{\mathrm{p}}=0.5{\mathrm{h}}_{\mathrm{v}}$, even better than the typical Voronoi distribution. The proposed design model has introduced an entirely novel approach that significantly enhances the product’s volume tessellation using routines that guarantee the validity of geometric and topologic entities. Uniaxial compression tests on lattice blocks highlighted the effect of the proposed approach on the mechanical properties of these structures, having shown particularly crucial repeatability and stability. Overall, the paper contributes to advancing the field of lightweight lattice structures through the novel design methodology and material characterization.

This work examines the mechanical behaviour of 3D-printed stochastic lattice structures fabricated using a semi-controlled design. A primary goal is to predict and optimize the mechanical response of these Acrylic Styrene Acrylonitrile (ASA) filament structures when subjected to compressive stress. By transitioning from a purely stochastic method to a semi-controlled tessellation approach within Rhinoceros 7 software, we effectively generated the proposed design models. This methodology results in mechanical responses that are both predictable and reliable. The design parameters, including nodal formation, strut thickness, and lattice generation based on a predefined geometric routine, are associated with the regulation of the relative density. This approach aims to minimize the effect of relative density on the actual stiffness and strength evaluation. Our findings are cantered on the compressive testing of structures, which were generated using a Voronoi population distributed along a parabolic curve. We analyzed their mechanical response to the point of failure by examining stress–strain fluctuations. Three distinct behaviour stages are observed: elastic range, plastic range, and collapse without densification. The influence of crosslink geometry on the elastic responses was highlighted, with parabolic configurations affecting the peak stresses and elastic line slopes. The structures exhibited purely brittle behaviour, characterized by abrupt local cracking and oscillatory plateau formation in the plastic stage.

The development of additive manufacturing techniques using a wide range of thermoplastic materials enables the investigation of material mechanical properties as a function of 3D printing process parameters. Printed models with complex geometries require the use of support material, followed by post-processing. Therefore, this paper examines the impact of primary post-processing on the mechanical properties of ASA type 1A test specimens, specifically the removed support material. Two batches of specimens were printed using FDM deposition technology, having been prepared for 3D printing by determining the layer thickness and the infill pattern. One batch was left at room temperature, while the other batch was melted in a liquid bath. After printing, the specimens were tested for tensile strength under ISO 527-2. The results showed an imperceptible difference between the two batches with the same ultimate tensile stress values. It can be concluded that the mechanical properties of ASA specimens remain unchanged when dissolved in a liquid bath composed of sodium hydroxide and eco-friendly tablets in 40 liters of water intended for dissolving the support material. ASA Specimens, FDM, Tensile Testing, Liquid Bath