Dynamic mechanical performances of enhanced anti-tetra-chiral structure with rolled cross-section ligaments under impact loading

• Published in: International journal of impact engineering Vol. 166; p. 104204
• Main Authors: Kai, Liu, Xiaofei, Cao, Peng, Zhang, WenWang, Wu, Ying, Li
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.08.2022; Elsevier BV
• Subjects: Anti-tetra-chiral honeycomb; Cross-sections; Energy absorption; Impact energy absorption; Impact loads; Impact velocity; Ligaments; Mathematical models; Negative Poisson's ratio; Plateau stress; Poisson's ratio; Shear modulus; Anti-tetra-chiral honeycomb; Negative Poisson's ratio; Impact energy absorption; Plateau stress
• ISSN: 0734-743X; 1879-3509
• DOI: 10.1016/j.ijimpeng.2022.104204

•1.A novel type of anti-tetra-chiral structure consisting of rolled ligaments is proposed.•2.Analytical expressions of the plateau stress under the low, medium and high velocity impact loading are derived.•3.The in-plane dynamic mechanical behaviors of the structures are investigated and compared. Compared with the traditional hexagonal honeycombs with positive Poisson's ratio, chiral metastructures have negative Poisson's ratio property, elevated transverse shear modulus and enhanced impact energy absorption performance, etc. In this study, the in-plane dynamic mechanical behaviors of ordinary anti-tetra-chiral honeycombs (ATH) consisting of straight ligaments with flat cross section and enhanced anti-tetra-chiral metastructures composed of rolled ligaments with curved cross section (RATH) are investigated and compared. The effects of geometric parameters of chiral structure, including α (the ratio of ligament length to ring radius),β (the ratio of ligament thickness to ring radius), γ (the ratio of ligament curvature to ring radius) and impact velocity on the plateau stress are analyzed with numerical simulation method. Theoretical formulas of the Poisson's ratio under the quasi-static compression and plateau stress are derived on the basis of the deformation modes of the metastructure at different impact velocities, and the results obtained from the analytical model are in good agreement with the numerical simulation results.