Additively manufactured three-dimensional lightweight cellular solids: Experimental and numerical analysis. (February 2023)

• Record Type: Journal Article
• Authors: Forés-Garriga, Albert; Gómez-Gras, Giovanni; Pérez, Marco A.
• Is Part Of: Materials & design. Volume 226(2023)
• Publication Date: 2023-02
• Subjects: Fused filament fabrication -- Triply periodic minimal surfaces -- Lattice -- Material properties -- Finite element analysis -- Homogenization; Materials -- Periodicals; Engineering design -- Periodicals; Matériaux -- Périodiques; Conception technique -- Périodiques; Electronic journals; 620.11
• DOI: 10.1016/j.matdes.2023.111641
• Languages: English
• ISSNs: 0264-1275

Abstract

Graphical abstract: Highlights: 3D cellular designs exhibit an improved and more isotropic mechanical performance than 2D patterns at similar levels of density. Although most of the 3D designs require support structures for their manufacturing, no increase in building time is noticed. The implementation of the sparse infill saves material, weight and printing time, while performance is slightly impacted. A novel and more consistent method for quantifying the isotropy of cellular solids fabricated with additive manufacturing technologies is provided. The homogenized numerical approach employing representative volume element properties saves important computation time with enough accuracy. Abstract: The development of cellular solids is one of the research fields in which additive manufacturing has made relevant progress in producing lightweight components and enhancing their performance. This work presents comprehensive research on the mechanical performance of fused filament fabricated three-dimensional lightweight cellular solids, including open-cell and closed-cell lattice designs and triply periodic minimal surfaces (TPMS), with different cell sizes and infill densities. The aim of this work is to determine the range and limits of the achievable mechanical behavior by employing different cell designs made from a single material and manufacturing technique. Experimental results obtained with cell designs fabricated with a high-performance polymer (PEI Ultem) showed wide ranges of effective stiffnesses from 1 to 293 MPa, strengths from 0.1 to 18.1 MPa, and densities from 0.066 to 0.541 g/cm 3 . Furthermore, two validated numerical approaches are provided to simulate their mechanical performance accurately. Moreover, a novel and robust index to quantify the isotropy of additively manufactured cellular solids based on the graphical representation of the homogenized stiffness tensor is proposed. Finally, experimental evidence states that the Shell-TPMS designs proved to be the most efficient cellular pattern, followed by the Skeletal-TPMS and the lattice configurations.