Bamboo‐Inspired Vascular Bundle Tubes via Additive Manufacturing for Enhanced Energy Absorption Under Complex Loading

ABSTRACT Lightweight energy‐absorbing structures are critically needed across engineering sectors. Conventional energy‐absorbing structures have an initial peak crush force that is too high and insufficient lightweighting. This study integrates additive manufacturing with biomimetic design to develop bamboo‐inspired vascular bundle tubes(VBT). Specimens fabricated from multiple materials underwent quasi‐static axial and radial compression testing. The results demonstrate superior energy absorption performance in carbon fiber–reinforced Polyethylene Terephthalate Glycol (PETG/CF) specimens. Structural optimization incorporating bamboo‐mimetic axial vascular arrangements enhanced specific energy absorption (SEA) through improved biomimetic fidelity. Process parameter studies revealed that reducing the layer height from 200 to 100 μm simultaneously increased SEA and reduced peak crushing force (PCF) under both loading conditions. Axial loading increased SEA by 30% and reduced PCF by 15%. In contrast, radial loading resulted in a 15% increase in SEA and a 20% reduction in PCF. This work establishes a synergistic material‐structure‐process strategy for high‐performance bio‐inspired energy absorbers, advancing impact protection technology.