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Materials Science in Additive Manufacturing Characterization of TPMS structures

A F

B

G

C

D

H

E

Figure 6. The manufacturing samples of Schwarz-P structures with different geometric parameters. (A) A0, A0.2, A0.4, A0.6, A0.8. (B) B0, B0.2, B0.4, B0.6,
B0.8. (C) C0, C0.2, C0.4, C0.6, C0.8. (D) D0, D0.2, D04, D0.6, D0.8. (E) E0, E0.2, E0.4, E0.6, E0.8. (F), (G), and (H) show the enlarged images of regions
A1, A2, and A3, respectively.
A2, and A3, respectively. As shown in Figure 6, all the polyline with many corners/vertices. Hence, the width
Schwarz-P structures were successfully fabricated; of the melt track of the small pore became much larger
however, inconsistent with the designs, several structures than we expected. Figure 7 depicts variations between the
(A0.4, A0.6, and A0.8) had closed pores. Theoretically, the actual pore size and the designed geometric parameters
Schwarz-P surface divides the space into two independent of the Schwarz-P structure. As the shape factor increases,
regions; however, there is width to the melt track, and the minimal pore size decreases; in contrast, as the unit
pores will close if the pore size is smaller than the width size increases, the minimal pore size increases. In addition,
of the melt track, resulting in many closed cavities an interesting phenomenon, as shown in Figure 7J, is that
filled with unmelted powder particles. Typically, the the structure had some broken holes, meaning that when
width of the Ti6Al4V melt track at the given processing the unit size was >5 mm, the Schwarz-P structure did not
parameters in this study (laser power = 120 W, scanning satisfy the AM constraints.
speed = 1100 mm/s, layer thickness = 0.03 mm, and
laser spot diameter = 0.05 mm) was 120 μm. However, as Figure 8 presents a comparison of the theoretical and
we found in our previous study , this width increased measured relative densities of the Schwarz-P structures.
[15]
significantly in the corner of the toolpath. The closed As shown in the figure, except for samples A0.4, A0.6, and
toolpath shown by the galvanometer scanning system was A0.8, the theoretically calculated results are consistent with
not a smooth curve with G2 continuous; rather, it was a the measured results. As shown in Figure 5, samples A0.4,

Volume 1 Issue 3 (2022) 6 http://doi.org/10.18063/msam.v1i3.17