Reliable comparison of multi-directional mechanical properties for biomimetic circle arc honeycombs

Abstract

Abstract Compared to straight honeycombs, curved honeycombs derived from biomimetic strategies typically exhibit superior mechanical properties and a broader tunable range. Consequently, there has been a surge in research focusing on curved honeycombs. However, few studies have concurrently designed multiple honeycombs for reliable comparisons, and little attention has been given to isotropy. In this study, circle arc walls were introduced to replace the straight walls of five classical honeycombs, thereby creating representative curved honeycombs for analysis. The numerical modeling method in ANSYS software was validated by experimentally testing 3D printed specimens of circle arc honeycombs. At the same mass and under loading conditions in different directions, it was found that the Young's modulus, yield strength, Poisson's ratio, and energy absorption of circle arc hexagon (CAH), circle arc square (CAS), circle arc triangle (CAT), circle arc re-entrant (CAR), and circle arc double-V (CAD) were assessed. Both experimental and numerical results revealed that CAH demonstrates superior energy absorption while maintaining a high degree of isotropy, characterized by all isotropic factors below 0.1 in mechanical properties. Notably, CAD exhibits a Negative Poisson's ratio (NPR) effect across all loading directions. These results provide benchmarks for future studies on curved honeycombs and guide further research in this field.