Mechanical and Numerical Analysis of Bio-Inspired Infill Structures in Additively Manufactured Thermoplastic Components.

Raihan Ahmed Redoy, Tonmoy Sarker, Zaber Mhamud, Nihal Sudman

Motivation

The rapid growth of additive manufacturing (AM), especially fused filament fabrication (FFF), enables the production of lightweight, customized, and cost-effective structural components. However, traditional infill patterns like rectilinear and honeycomb often fall short in providing optimal strength-to-weight ratios and energy absorption under multi-axial loading. Nature-inspired geometries, such as fish scales and spider webs, offer potential solutions by combining stiffness, flexibility, and lightweight efficiency. This study explores the impact of bio-inspired infills and various filament materials (e.g., ABS, PETG, TPU, carbon fiber composites) on mechanical performance. Through experimental testing and finite element modeling, it aims to enhance understanding of material-structure interactions, enabling optimized designs for industrial applications.

Possible Outcome

This research is expected to demonstrate that bio-inspired infill structures such as fish scale, leaf vein, spider web,and multi sprial provide distinct advantages over conventional patterns in terms of strength-to-weight efficiency and energy absorption. The outcomes will likely show that each infill exhibits unique mechanical benefits depending on the applied loading mode and material—for instance, TPU structures may excel in impact resistance and flexibility, while carbon-fiber composites achieve superior stiffness and strength. By correlating relative density with tensile, flexural, compression, and impact properties, specific performance metrics such as strength-to-weight index and specific modulus will be established. Finite element simulations are anticipated to validate experimental results within acceptable error margins, also highlighting critical stress concentration zones and failure modes consistent with fracture surface analysis. Overall, the study will deliver practical guidelines on selecting bio-inspired architectures for targeted industrial applications, while contributing novel insights into the structure property relationships of 3D-printed polymers and composites.

Graphical Representation

Key Points

• Developing the sample containing the selected infill structure using different thermoplastic materials (ABS, PEtG, TPU, CF- Filament).
• Developing the sample containing the selected infill structure using different thermoplastic materials (ABS, PEtG, TPU, CF- Filament).
• Performing tensile, compression, impact, and flexural tests to evaluate mechanical properties and to validate the mechanical properties, the numerical analysis will be done.