Page 50 - eBook_Proceedings of the International Conference on Digital Manufacturing V2

Proceedings of the International Conference on Digital Manufacturing –
Volume 2

the most uneven stress distribution in the lattice. This means that
Octet and Kelvin unit cell will fail more evenly under a design
load and offer the most optimum mass distribution for structural
applications. Among the geometries considered, the Gyroid
demonstrates the best performance due to its dual surface–volume
characteristics. The stress concentration occurs at the contact
point of lattice with the skin surface regardless of the lattice
geometry used.

The visualisations of above results showed the strain
developed in each lattice shows that HX HC lattice have the most
significant deformation. This means that HX HC lattice will
undergo shape change due to applied stresses. TRI HC behave
conversely to HX HC, making it more resilient to shape change.
From the simulations, equivalent strain (Table 5) and stress values
(Table 6) have been extracted. The stress/mass ratio for each
lattice configuration have been calculated and plotted against the
applied displacement. Figure 18 represents the strain behaviour
in response to the applied displacements.

Table 5: Equivalent Strains (in mm/mm) of different unit cells
beams subjected to multiple displacements (i.e. 2mm, 5mm, 10mm,
15mm, 20mm) in vertical direction.

Displacement (mm)
Lattice 2 5 10 15 20
Structure
Strain (mm/mm)
BCC 0.0421 0.1060 0.2120 0.3180 0.4241
FCC 0.0420 0.1050 0.2100 0.3150 0.4200
Kelvin 0.0412 0.1031 0.2062 0.3093 0.4124
Octet 0.0413 0.1149 0.2299 0.3448 0.4597
HX HC 0.0996 0.2490 0.4980 0.7471 0.9961
TRI HC 0.0332 0.0831 0.1662 0.2494 0.3325
Fluorite 0.0378 0.0945 0.1890 0.2835 0.3780
Diamond 0.0362 0.0905 0.1811 0.2716 0.3621
Gyroid 0.0343 0.0854 0.1709 0.2563 0.3418

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