A new hybrid lattice structure with improved modulus, strength and energy absorption properties

In this paper, a hybrid octagonal simple-cubic (OSC) lattice structure is obtained by combining the cell configurations of the bending-dominated octagonal lattice and the stretching-dominated SC lattice. Finite element (FE) numerical models of the three lattice structures (octagonal, octet and OSC lattice) are established and the axial quasi-static compression simulations are performed. In addition, a theoretical model is established to predict the plateau stress of the OSC lattice with different volume coefficients k. Satisfactory consistency is achieved between the results of the theoretical model and those from FE numerical simulations. The results show that the elastic modulus, the compression strength and the energy absorption capacity of the proposed OSC lattice are respectively increased by 233%, 86%, and 25% compared with the octagonal lattice under the same relative density conditions, while those values are respectively 212%, 34%, and 20% compared with the octet lattice, high-lighting the superior mechanical properties of the hybrid OSC lattice. The effects of volume coefficient k and loading direction on the compression behavior of the OSC lattice were parametrically analyzed. The results show that the volume coefficient k is inversely related to the mechanical properties, and an anisotropic characteristic is exhibited in terms of the compression behavior of the OSC lattice structures.

Automated summary

This paper presents a hybrid octagonal simple-cubic (OSC) lattice structure obtained by combining the bending-dominated octagonal lattice and the stretching-dominated SC lattice. Finite element (FE) numerical models and theoretical predictions are established to analyze the mechanical properties and compression behavior of the OSC lattice. The results show that the OSC lattice has significantly improved elastic modulus, compression strength, and energy absorption capacity compared to the octagonal and octet lattice structures.