A topological approach for optimizing the dimensional properties of various bioinspired periodic type honeycomb latticed carbon fiber reinforced glycol-modified poly (ethylene terephthalate) composite materials

The present research efforts are directed toward investigating dimensional stability, focusing on bio-inspired periodic honeycomb lattice structures within carbon fiber reinforced glycol-modified poly ethylene terephthalate (PETG) composites. These samples are fabricated using extrusion-based 3D printing, with topological parameters such as shell thickness (ST), unit cell type (UCT), wall thickness (WT), unit cell orientation (UCO), skewing angle (SA), and unit cell size (UCS) being manipulated across three different levels. The experimental findings indicate that achieving the lowest dimensional length error is attainable under specific conditions, including a smaller ST of 0.5 mm, a square UCT, a WT of 0.5 mm, a UCO of 90^°, a SA of 0^°, and a UCS of 4 mm. Analyzing the results with ANOVA reveals that UCT (28.82%) and WT (18.73%) exert the most significant influence on the dimensional stability response. The regression model closely aligns with experimental outcomes, with an error percentage of 3%, rendering it suitable for large-scale customization. Under the optimized topological parameters, carbon fiber-reinforced PETG latticed composites exhibited a dimensional length error of 0.292 mm and a compressive strength of 21.56 MPa. Fractography analysis revealed a brittle mode of fracture across all samples, indicating their stiffness and strength, especially when compared to samples with lower wall thickness. These findings suggest that the designed carbon fiber-reinforced PETG latticed composite material holds potential for use in minor surgical orthotic and prosthetic applications. Highlights • Bio-inspired periodic honeycomb lattice structured PETG composites. • Topological optimization on the dimensional properties. • Taguchi optimization is performed on design-based lattice structures. • Unit cell type has highest contribution of 28.82% on dimensional properties.