PSI - Issue 83

Wong Kam Chee et al. / Procedia Structural Integrity 83 (2026) 14–27

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a)

b)

c)

d)

Figure 7. Directional unit cells homogenization (a) Schwarz P; (b) Gyroid; (c) H1; (d) H2

Table 7. Maximum and minimum directional stiffness of the unit cells Max (MPa) Min (MPa) Difference (%) G 6.2427 x 10 3 5.4528 x 10 3 12.65 P 6.7923 x 10 3 2.6979 x 10 3 60.28 H1 4.7722 x 10 3 3.4650 x 10 3 27.39 H2 4.8814 x 10 3 3.0910 x 10 3 36.68

Figure 8 shows the unit cell homogenisation maximum displacement, which explains the mechanical properties of the lattices under directional shear stress. Gyroid has X, Y, Z axial displacements of 5.9764mm, 5.9904mm, and 5.9433mm and a maximum axial displacement difference of 0.79%. Shear displacements of Gyroid in XY, XZ, and YZ directions of 5.6076mm, 5.2505mm, and 5.6567mm, respectively and a maximum shear displacement difference of 7.18%. Schwarz P has X, Y, Z axial displacements of 5.7393mm, 5.5696mm, and 5.7195mm and a maximum axial displacement difference of 2.96%. Shear displacements of Gyroid in XY, XZ, and YZ directions of 5.0989mm, 5.0991mm, and 5.0912mm, respectively and a maximum shear displacement difference of 0.15%. H1 has X, Y, Z axial displacements of 7.4680mm, 7.5034mm, and 7.3214mm and a maximum axial displacement difference of 2.43%. Shear displacements of H1 in XY, XZ, and YZ directions of 7.7408mm, 6.3741mm, and 7.5554mm, respectively and a maximum shear displacement difference of 17.66%. H2 has X, Y, Z axial displacements of 7.2858mm, 7.3631mm, and 7.1750mm and a maximum axial displacement difference of 0.96%. Shear displacements of Gyroid in XY, XZ, and YZ directions of 8.8146mm, 7.1994mm, and 8.6706mm, respectively and a maximum shear displacement difference of 18.32%. Gyroid lattice’s displacement for X, Y, and Z direction has similar values, indicating a near isotropic axial response, while the shear in XY, XZ, and YZ direction has slightly less displacement, which means it has a strong shear resistance. Schwarz P has the lowest displacement in all X, Y, Z, XY, XZ, and YZ directions, which represents the highest stiffness among the lattices. However, it has a slightly higher Y-direction stiffness, which is suitable for situations where unidirectional loading dominates. H1 has the highest displacement in X, Y, and Z directions among the lattices, likely due to the poor transition in the design, but it has high shear resistance in the XZ direction. H2 has a lower displacement in X, Y, and Z directions, but it has a lower shear resistance in XY, XZ, and YZ directions in exchange.