Understanding the superior mechanical properties of hollow-strut metal lattice materials. (15th April 2023)

• Record Type: Journal Article
• Authors: Zhong, H.Z.; Song, T.; Li, C.W.; Das, R.; Gu, J.F.; Qian, M.
• Is Part Of: Scripta materialia. Number 228(2023)
• Publication Date: 2023-04-15
• Subjects: Lattice material -- Additive manufacturing -- Hollow strut -- Yield strength -- Deformation mechanism; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2023.115341
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: Intricate hollow-strut metal lattice materials are an emerging class of novel metallic cellular materials enabled by additive manufacturing. This work shows that hollow-strut Ti-6Al-4V lattice materials are consistently stronger and stiffer (up to 60% better) than their solid-strut counterparts of the same relative density, both experimentally and through finite element analysis (FEA). The underlying reasons are investigated using analytical models derived from the Timoshenko-beam theory, which considers deformation by concurrent stretching, bending and shear, rather than the single-mode deformation mechanism assumed by the Gibson-Ashby model. Hollow-strut lattices exhibit higher resistance to bending than solid-strut lattices at the same strut length and relative density, thereby leading to increased strength and stiffness. Hollow-strut metal lattices offer an unusual option for lightweight designs, with better mechanical properties at the same or lower density than solid-strut metal lattices. Graphical abstract: Image, graphical abstract