Influence of density gradient and hybrid effect on quasi-static axial crushing behavior of lattice cylindrical structures. (May 2023)

• Record Type: Journal Article
• Authors: Zhao, Wanqi; Liu, Tao; Chen, Liming; Guo, Yongguang; Pan, Xin; Zhu, Shaowei; Li, Weiguo
• Is Part Of: Thin-walled structures. Volume 186(2023)
• Publication Date: 2023-05
• Subjects: Lattice cylindrical structure -- Density gradient -- Hybrid effect -- Sandwich structure -- Energy absorption; Thin-walled structures -- Periodicals; 690.1
• DOI: 10.1016/j.tws.2023.110720
• Languages: English
• ISSNs: 0263-8231

Abstract

Abstract: Uniform/gradient lattice cylindrical structures (ULCS/GLCS) and hybrid uniform/gradient lattice cylindrical structures (HULCS/HGLCS) are innovatively designed and fabricated. The axial crushing behaviors of these four-type cylindrical structures are investigated by the quasi-static axial compression experiments and numerical simulations. The influence of the density gradient and the hybrid effect (metal skin+ABS core) on the deformation mode, loading capacity, and energy absorption of the lattice cylindrical structures are elaborated systematically. The results show that the gradient design realizes the function of regulation and controllability of the structural deformation. The softer layers (with smaller relative density) in GLCS begin to deform first and then gradually extend to the harder layers (with larger relative density). And it effectively reduces the initial peak compression force ( PCF ), and makes the load more stable on the premise of energy absorption. However, unstably catastrophic failures are observed before the final densification in both ULCS and GLCS during the compression due to the brittleness of the ABS material and the compression–expansion​ deformation of structure. For HULCS/HGLCS, it presents progressive crushing mode and overcome the unstably catastrophic failure due to the ductility and constraint of the metal skins. The effect of "1 ＋ 1 > 2" on energy absorption from hybrid effect is achieved in HULCS/HGLCS, in which the EA of HULCS and HGLCS increases by 74.62% and 100.78% comparing the sum of all components individually compressed. Moreover, the progressive peak with increasing trend of HGLCS demonstrated that the hybrid design enhances the advantages of gradient design in sandwich structures. Highlights: Uniform/gradient lattice cylindrical structure (ULCS/GLCS) and hybrid uniform/gradient lattice cylindrical structure (HULCS/HGLCS) is presented. The gradient design in GLCS realizes the function of regulation and controllability of the structural deformation, and makes the load more stable. For HULCS/HGLCS, the hybrid design effectively overcomes the structural catastrophic failure, achieve the effect of "1+1>2" in energy absorption, and enhances the advantages of gradient design in sandwich structures.