Page 113 - MSAM-4-2

Materials Science in Additive Manufacturing Impact of cell angle on AlSi10Mg structures

stiffness characteristics remain similar across different maximum energy absorption capacity is reached. These
impact energy levels, suggesting that impact energy has results highlight the importance of further optimizing
a negligible effect on the linear stiffness of the structure. the lattice design to enhance the failure resistance of the
However, both peak force and energy absorption Dodeca-A P80 structure.
exhibit significant variations with increasing impact The analysis of fracture modes in the LPBF-fabricated
energy. At impact energy of 41 J (M1 in Table 2), the
force-displacement curve of the Dodeca-A P80 sample AlSi10Mg porous structures provides critical insights into
initially exhibits a linear elastic response, followed by a their mechanical performance under impact loading.
brief oscillation phase before transitioning into a fully During impact, the porous structure undergoes collapse,
compacted state. The small displacement and absence resulting in the formation of shear fractures with varying
of significant support rod fractures indicate that the inclinations, as illustrated in Figure 8A. Surrounding one
applied impact energy is insufficient to cause substantial edge, obvious cleavage planes are evident throughout
structural damage, suggesting that the Dodeca-A P80 the impact fracture (highlighted by the red contour in
structure can effectively redistribute stress without Figure 8B), primarily observed at the outer edge, where
failure under low-energy impacts. In contrast, under rapid failure occurs due to swift crack propagation. In
an impact energy of 124 J (M2 in Table 2), the sample contrast, the central section of the fracture exhibits a
exhibits a prolonged oscillation phase with an extended substantial area of dimples, indicative of ductile fracture
contact duration before reaching ultimate failure. behavior (Figure 8C). This observation suggests that initial
The structure undergoes noticeable fractures, and the deformation and energy absorption occur at the onset
energy-displacement curve gradually increases until the of impact, where crack propagation leads to microvoid

A B

Figure 7. Mechanical response and energy absorption of Dodeca-A structures (A) Force-displacement curves of the laser powder bed fusion-built AlSi10Mg
Dodeca-A P80 structure under different impact energies and (B) energy-displacement curves showing energy absorption at varying impact energies
Abbreviation: Dodeca: Dodecahedral

A B C

Figure 8. Microscopic morphology of the impact fracture of the dodecahedral-A P80 structure in laser powder bed fusion-fabricated AlSi10Mg.
(A) Schematic shear fractures, (B) cleavage planes at the outer edge, and (C) dimpled morphology in the central region (initiation and propagation region).
Scale bars: 5 μm and 500 μm, magnification: 18367×, 80×
Abbreviations: SEM: Scanning electron microscopy

Volume 4 Issue 2 (2025) 9 doi: 10.36922/MSAM025130019