About this Abstract |
| Meeting |
MS&T26: Materials Science & Technology
|
| Symposium
|
Additive Manufacturing: Architected Structures and Multifunctional Metamaterials
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| Presentation Title |
Effect of Fused Deposition Modeling-Induced Defects and Heat Treatment on the Mechanical Response of PLA Lattices |
| Author(s) |
Aditya Chauhan, Kirk Duvall Johnson, Garrett Pataky, Huijuan Zhao |
| On-Site Speaker (Planned) |
Aditya Chauhan |
| Abstract Scope |
Additive manufacturing (AM) enables fabrication of architected polymer structures with tailored topology and high mechanical efficiency. Lattice architectures are attractive for engineering applications because of their high specific stiffness, strength-to-weight ratio, and energy-dissipation capacity. Although their quasi-static behavior has been extensively characterized, fatigue damage accumulation and crack initiation in FDM-printed lattices remain insufficiently understood. In this study, polylactic acid (PLA) specimens were fabricated by fused deposition modelling to experimentally evaluate fatigue behavior in printed lattice architectures. Tensile and compressive tests on dogbone specimens characterized the base material response and provided calibration data for finite element modelling (FEM). A 2.5D octet-style lattice tensile specimen, designed following ASTM E08, was first heat-treated at 65°C for 35 min to reduce lack-of-fusion defects. Stress-controlled fatigue tests were then performed at R = 0.1 until strut-level crack initiation. An extended finite element model (XFEM) characterized damage accumulation and predicted crack initiation locations. Digital image correlation (DIC) quantified strain localization and damage evolution. Future work will extend this methodology to 3D octet lattices to determine whether the observed damage mechanisms remain consistent in more complex geometries. |