Effect of infill pattern on the mechanical properties and stress relaxation behavior of 3D printed PEEK
Year: 2025
Type: article
Abstract: Polyether ether ketone is prized for its outstanding mechanical strength, biocompatibility, and high-temperature stability, which underpin its widespread use in aerospace and biomedical sectors. Additive manufacturing via fused filament fabrication brings additional benefits for polyether ether ketone components—reduced material consumption, part-level customization, and expanded geometric freedom—yet the long-term load-bearing behavior of printed polyether ether ketone remains underexplored. This study systematically evaluates how eight representative infill architectures (line, grid, honeycomb, triangular, gyroid, Hilbert-curve, concentric, and random) at ∼30% nominal relative density control both instantaneous tensile behavior and time-dependent stress relaxation. Tensile testing shows that honeycomb and grid infills consistently outperform conventional line and triangular patterns, delivering up to a 25% increase in elastic modulus and yield strength. Long-duration relaxation experiments reveal that these architectures also preserve higher residual stresses after two hours, indicating improved viscoelastic stability. Correlative micro-computed tomography imaging and finite-element modelling demonstrate that the superior performance arises from more uniform stress distributions and optimized load-transfer pathways; stress–strain responses from finite element modeling closely reproduce the experimental curves, validating the structural interpretations. Together, these results provide direct design rules for infill selection in load-bearing, long-service polyether ether ketone parts (aerospace structural components, long-term biomedical devices, seals and clamping elements) and inform international research on architected polymer mechanics by quantifying trade-offs between stiffness, strength and viscoelastic retention.
Authors: Qian Sun, Sai Teja Potu, Jianhao Man, Xiaojun Tan, Kaiyang Yin, Bo Cao, Christoph Eberl
Language: English
Subfield: Automotive Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,640
Awards: G149124214, G2651562179, G2664107761, G2788535355, G2920390530, G3273545289, G3380425172, G3512348562, NSF: Additive Fertigung von ermüdungsresistenten, metallischen Programmierbaren Metamaterialien, G4014434561, G413164177, G4350353591, G5090764095, G5178844588, G5422198267, G5466434173, G6475948386, G7284107121, EXC 2193: Lebende, adaptive und energieautonome Materialsysteme (livMatS)
OpenAlex ID: W4415534536