Design, Manufacturing, and Analysis of Periodic Three-Dimensional Cellular Materials for Energy Absorption Applications: A Critical Review

Abstract

Cellular materials offer industries the ability to close gaps in the material selection design space with properties not otherwise achievable by bulk, monolithic counterparts. Their superior specific strength, stiffness, and energy absorption, as well as their multi-functionality, makes them desirable for a wide range of applications. The objective of this paper is to compile and present a review of the open literature focusing on the energy absorption of periodic three-dimensional cellular materials. The review begins with the methodical cataloging of qualitative and quantitative elements from 100 papers in the available literature and then provides readers with a thorough overview of the state of this research field, discussing areas such as parent material(s), manufacturing methods, cell topologies, cross-section shapes for truss topologies, analysis methods, loading types, and test strain rates. Based on these collected data, areas of great and limited research are identified and future avenues of interest are suggested for the continued maturation and growth of this field, such as the development of a consistent naming and classification system for topologies; the creation of test standards considering additive manufacturing processes; further investigation of non-uniform and non-cylindrical struts on the performance of truss lattices; and further investigation into the performance of lattice materials under the impact of non-flat surfaces and projectiles. Finally, the numerical energy absorption (by mass and by volume) data of 76 papers are presented across multiple property selection charts, highlighting various materials, manufacturing methods, and topology groups. While there are noticeable differences at certain densities, the graphs show that the categorical differences within those groups have large overlap in terms of energy absorption performance and can be referenced to identify areas for further investigation and to help in the preliminary design process by researchers and industry professionals alike.

Keywords: additive manufacturing; cellular materials; energy absorption; lattice topology; relative density.

Figure 4

Distribution of topologies investigated in the literature. Bars for maximum 3 values filled with orange speckle, bars for minimum value filled with blue diagonal lines, and all other bars filled in gray. “TPMS” has a more detailed breakdown in a separate figure; “Circular” also includes variations in the strut-based circular topology (e.g., semi-circle, cross semi-circle); “Diamond” includes “Dfcc”; and “Other” includes topology-optimized geometries as well as unique geometries created for the purposes of the paper of interest (e.g., “Twisted-octet”, “CLL”, “cross-chiral honeycomb”) and plate-/shell-based topologies (e.g., “BCC-6H”, “BCC-12H”) are also grouped within this category. Numbers in brackets preceding topology names are associated with the respective numbered topology unit cell view. nTopology (nTop, New York City, NY, USA) [178] was utilized to create the majority of the illustrations of the strut-based cells; Ansys SpaceClaim (Ansys Inc., Canonsburg, PA, USA) [179] was utilized for the circular and rhombicuboctahedron cells.

Figure 5

Distribution of TPMS topologies investigated in the literature. Bars for maximum 3 values filled with orange speckle, bars for minimum value filled with blue diagonal lines, and all other bars filled in gray. Here, the “Other” category includes TPMS-like sheet topologies, TPMS-BCC, “FRD”, and “IWP”. Images of TPMS topologies are provided above the respective bar value and include illustrations for (left) sheet-based/matrix phase and (right) a version of the skeletal-based/network phase. nTopology (nTop, New York City, NY, USA) [178] was utilized to create the illustrations of the TPMS topologies.

Figure 11

Legend for symbols in remaining figures of this section. Number in bracket refers to paper as listed under “Num.” column in Table A1, which can be used to locate the direct reference in question.

Figure 1

Average number of publications reviewed and summarized per year over specified time range.

Figure 2

Distribution of material types utilized in the literature. Bars for maximum 3 values filled with orange speckle, bars for minimum value filled with blue diagonal lines, and all other bars filled in gray. Note that here, “Polymer/Resin” does not include nylon polymers since it is provided as a separate category, and the “Composite” category includes materials such as carbon fiber-reinforced and glass fiber-reinforced nylon materials.

Figure 3

Distribution of manufacturing methods utilized in the literature. Bars for maximum 3 values filled with orange speckle, bars for minimum value filled with blue diagonal lines, and all other bars filled in gray. Note that here, “PBF/LPBF”, “EBM”, “DMLS”, “SLM”, and “SLS” are all listed as separate categories, where papers were classified based on the terminology they used and/or the type of 3D printer listed. The “Other” category includes collimated UV, water jet cutting, and those processes unspecified in the paper of interest.

Figure 6

(Left) Distribution of the literature investigating multiple different topologies in one publication; (Right) distribution of number of topologies investigated when investigating more than one topology.

Figure 7

Distribution of cross-sectional shapes for strut-based topologies investigated in the literature. Slice for maximum value filled with orange speckle, slice for minimum value filled with blue diagonal lines, and all other slices filled in gray.

Figure 8

Distribution of methods for characterization. Slice for maximum value filled with orange speckle, slice for minimum value filled with blue diagonal lines, and all other slices filled in gray.

Figure 9

Distribution of the literature investigating (quasi-)static versus dynamic loading rates. Slice for maximum value filled with orange speckle, slice for minimum value filled with blue diagonal lines, and all other slices filled in gray.

Figure 10

Common profiles of impactors. (a) Flat, (b) ogival, (c) hemispherical, and (d) conical.

Figure 12

Specific energy absorption by volume versus lattice part density with highlights for select categories of parent material types. The “Polymer” group includes PLA, ABS, etc., but excludes nylon.

Figure 13

Specific energy absorption by volume versus lattice part density with highlights for select categories of manufacturing methods.

Figure 14

Specific energy absorption by volume versus lattice part density with highlights for select categories of truss-based topologies. TPMS topology highlights shown in Figure 16 for these axis variables.

Figure 15

Specific energy absorption by mass versus lattice relative density with highlights for select categories of truss-based topologies. TPMS topology highlights shown in Figure 17 for these axis variables.

Figure 16

Specific energy absorption by volume versus lattice part density with highlights for select categories of TPMS topologies. Truss-based topology highlights shown in Figure 14 for these axis variables.

Figure 17

Specific energy absorption per mass versus lattice relative density with highlights for select categories of TPMS topologies. Truss-based topology highlights shown in Figure 15 for these axis variables.