Mechanical properties and energy absorption performance of bio-inspired dual architecture phase lattice structures

In this paper, a novel dual architecture phase lattice (DPL) structure consisting with hard and soft phases is proposed, and their mechanical properties as well as the deformation features under compression are investigated. Firstly, two different types of basic cubic cells are selected as the constitution phases, and the DPLs with different arrangements are then constructed by additive manufacturing. Quasi-static compression tests and numerical simulations are performed to explore the deformation patterns and stress-strain responses. The compressive strength, plateau stress and the specific energy absorption of the DPLs are characterized. The effects of base material fracture, rod diameter and the cell arrangements on the mechanical responses are explored. Results show that the deformation and failure initiate in the matrix phase and trigger the embedding of the reinforcing phase into the crushed regions. The fracture of the rods results in a lower stress level and more serious fluctuations in the stress-strain responses. Increasing the rod diameter is an effective approach for enhancing the compressive strength and specific energy absorption. Introducing appropriate agreements of reinforcement phases can result in 112% and 37% increments for the compression strength and specific energy absorption, respectively. The findings of this work can facilitate the designs of lattice structures with outstanding mechanical properties and energy absorption performances.