Synergetic control mechanism for enhancing energy-absorption of 3D-printed lattice structures

• Published in: International journal of mechanical sciences 2024-01, Vol.262, p.108711, Article 108711
• Main Authors: Liu, Xuefeng, Wang, Yihao, Liu, Xincheng, Ren, Yiru, Jiang, Hongyong
• Format: Article
• Language: English
• Subjects: Energy-absorption; Failure mode; Lattice structure; Synergetic control mechanism
• ISSN: 0020-7403; 1879-2162
• DOI: 10.1016/j.ijmecsci.2023.108711

•Great mechanical properties of lattice based on synergism with gradient- and Orowan-strengthening mechanism.•Improve the SEA of lattice with Gradient-Orowan synergism by 31.0%∼35.1% as compared with any other lattices.•Propose the modified Rule of Mixtures (m-ROM) to predict the effective stiffness of layers in the gradient lattice.•Stronger interactions between RP boundaries for the closer RP spacing to affect failure modes.•Provide a controllable mechanical design method of lattice by introducing Gradient-Orowan synergism. It is difficult for controlling the failure mechanisms to improve the mechanical properties of lattice structures in a specified way. To this end, inspired by biological tissue/alloy microstructure, a novel synergetic control mechanism with gradient- and Orowan-strengthening is proposed to enhance energy-absorption (EA) of lattice. Gradient, Orowan and Grad-Oro lattices with different Reinforcement Phase (RP) spacing are designed and manufactured by 3D-printing with little defect. By experiments, simulations and theoretical analysis, compressive behaviors and failure modes of designed lattices are studied to explore the effects of synergetic control mechanism on mechanical properties. Results show that a 31.0%∼35.1% higher SEA than Matrix lattice is identified for Grad-Oro lattices which also surpass Orowan or Gradient lattices. Then, the transitional failure mechanisms of lattices are revealed to explain the improvement. It is illustrated that Zigzag shear-path induced by the Gradient-Orowan synergism can dissipate more energy than any single mechanism (bypassing shear-path or progressive collapse). It is finally found that closer RP spacing brings about stronger interactions between RP boundaries to affect failure modes like the grain boundary strengthening. This novel concept and structural design method greatly contribute to controllable mechanical design of lattice. [Display omitted]