Mechanical characterization of Al2O3 twisted honeycomb structures fabricated by digital light processing 3D printing

Abstract

Inspired by the double-helix structure of biological DNA, low-volume fraction and high-strength Al2O3 twisted honeycomb structures with characteristics similar to those of helical structures in the z-axis were prepared by digital light processing 3D printing technology. As the twist angle increased, the compressive strength of the fabricated Al2O3 structure decreased, and the deformation mechanism of the Al2O3 structures gradually changed from stretching-dominated to bending-dominated, which can be predicted by the Gibson–Ashby model. The relationship between the effective elastic modulus and the volume fraction that can be modified by varying the wall thickness was described by the Pabst–Gregorova exponential relationship. The compressive strength of the Al2O3 structure with a twist angle of 0° can reach 62.4 MPa at a volume fraction of 13.3%, providing guidance to optimize lightweight structures of ceramics.