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Materials Science in Additive Manufacturing Topology optimization of an aluminum bicycle pedal
crank using laser powder bed fusion

While melt pool size was not the primary focus of this In this study, melt pool dimensions were analyzed using
study, it is essential for understanding heat distribution ImageJ software (Figure 8), revealing an average width (W)
and solidification behavior during LPBF. As demonstrated of 153.6 µm (in purple) and a depth (h) of 60.7 µm (in
in previous studies, [1,2] melt pool dimensions significantly green). These values were obtained from the laser scan
influence material properties, including porosity, strength, tracks on the last layer, as these tracks are unaffected by
and microstructural integrity. To accurately characterize remelting during subsequent layers. For a more detailed
these effects, it is recommended that future investigations characterization of the melt pool, including its chemical
employ single-track experiments, which provide more composition and morphological changes, we recommend
precise measurements of the melt pool, especially at the utilizing advanced techniques such as transmission
top surface (last layer), where no subsequent layers affect electron microscopy (TEM), and SEM with electron
39
the measurements. backscatter diffraction. 38,40,41
1 A novel paradigm for feedback control in LPBF: layer-wise 3.2. Simulation of static test
correction for overhang structures
E. Vasileska, A. G. Demir, B. M. Colosimo and B. Previtali The topologically optimized component (Figure 2), with an
Advances in Manufacturing 2022 Vol. 10 Issue 2 Pages 326-344 initial mass of 886 g, underwent a static load test under a
DOI: 10.1007/s40436-021-00379-6 1300 N load. The maximum local stress during static loading
2 A Review on Discrete Element Method Simulation in Laser
Powder Bed Fusion Additive Manufacturing under 1300 N is 214 MPa, which is below the yield strength
H. Chen, Y. Sun, W. Yuan, S. Pang, W. Yan and Y. Shi of AlSi10Mg (240 MPa). This results in a safety factor of
Chinese Journal of Mechanical Engineering: Additive Manufacturing 1.12. While no plastic deformation is expected under typical
Frontiers 2022 Vol. 1 Issue 1 Pages 100017 loading conditions, elastic deformation may still occur,
DOI: https://doi.org/10.1016/j.cjmeam.2022.100017
particularly in the lattice structure. Lattice structures, designed
to optimize material usage and reduce weight, behave
differently under load than solid components due to internal
voids. These internal voids lead to localized strain, resulting
in elastic deformation without exceeding the yield strength.
This deformation is reversible, and the material returns to its
original shape once the load is removed. While the simulation
suggests that the component will not undergo permanent
deformation under the applied load, the safety factor derived
from stress analysis may vary depending on the specific
criteria and calculation method. Simulation plays a crucial
role in predicting the mechanical behavior of components
and guiding design adjustments before manufacturing.
However, static simulations are not a substitute for empirical
mechanical testing. Fatigue testing remains essential to ensure
Figure 6. Experimental procedure for microstructural and mechanical
characterization

Figure 7. An optical micrograph of melt pools perpendicular to the build
direction of AlSi10Mg shows the characteristic fish-scale pattern, with
elongated cells along the laser scan path and equiaxed cells perpendicular
to it. Scale bar: 100 µm Figure 8. Melt pools’ dimensions. Scale bar: 100 µm

Volume 4 Issue 1 (2025) 6 doi: 10.36922/MSAM025040003