A geometry-process-property framework for FDM-fabricated TPU energy-absorbing metamaterials
摘要
Mechanical metamaterials can deliver exceptional energy absorption through architecture, yet many design studies overlook manufacturability and many print-and-test studies do not produce transferable design rules. Here, we present a print-constrained geometry-process-property framework for fused deposition modeling (FDM)-fabricated thermoplastic polyurethane (TPU) lattices. The framework embeds manufacturability limits at the CAD stage, validates printed behavior through dimensional metrology, mechanical testing, and finite element analysis, and converts the results into normalized design fingerprints. Four curvilinear unit-cell families (two re-entrant and two convex) were fabricated in TPU-95A at internal angles of 35°, 40° and 45°. Quasi-static compression was used to quantify elastic modulus, ultimate compressive strength, volumetric and specific energy absorption, efficiency, ideality, resilience, and pre-densification operating windows relevant to protective and wearable applications. Increasing the internal angle, particularly to 45°, increased stiffness and energy capacity, whereas unit-cell geometry governed deformation-mode sequencing, plateau behavior, and the partitioning between recoverable and dissipative energy. These relationships are distilled into radar-chart fingerprints that enable selection of manufacturable architectures and tuning of force transmission versus energy absorption. As a translational demonstration, the maps were used to guide lattice selection for a pressure garment for scar therapy. The framework provides a practical route to process-aware architecture selection and reusable design libraries for energy-absorbing lattices.