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International Journal of Bioprinting Tunable anisotropic gyroid bioscaffolds

Figure 7. Comparative analysis of specimens fabricated using different processes. (a) X-ray diffraction (XRD) pattern for SHPS120m, RCS120m, and
MW120m. (b) The stress–strain curve of the ceramic cube specimens prepared through different heating profiles.

increase, respectively, compared to MW120m. Additionally, a rough surface morphology, which is primarily due to the
compared to RCS120m, SHPS120m specimens showed staircase artefacts formed from pixelated light and layer-
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a remarkable 336% increase in compressive strength and by-layer forming mechanism of the DLP technology.
a 28% increase in Young’s modulus. The SHPS process As observed, the pixelated morphology became more
leads to a much denser specimen with minimized defects, pronounced after sintering, but no signs of cracks, voids,
thereby significantly enhancing the mechanical properties. and delamination of layers were observed. This suggests
Therefore, this process was employed for the post-thermal that the gyroid structures were successfully sintered,
treatment of DLP-printed sheet gyroid structures to ensure resulting in a dense specimen through the proposed SHPS
the quality of the 3D ceramic scaffold. The compressive method. The wall thickness and the pore diameter of the
strength and Young’s modulus of the specimens are sheet gyroid structures were also investigated using ImageJ,
summarized in Table 2. and the results are summarized in Table 3. As ϕ increased,
the wall thickness increases, measuring at 274.1 ± 15.5,
3.3. Characterization of DLP-printed gyroid scaffold 374.6 ± 15.1, and 475.7 ± 25.5 µm for 40VF-gy, 50VF-gy,
Figure 8a shows the SEM images of the sheet gyroid and 60VF-gy, respectively. Conversely, the pore diameters
structures before and after the SHPS process, with different decreased as the ϕ increased, with values of 674.3 ± 24.9,
value of ϕ. The lamellar facets were examined to identify 576.8 ± 15.0, and 528.4 ± 28.6 µm for 40VF-gy, 50VF-gy,
any structure defects. The DLP-printed sample displayed and 60VF-gy, respectively.

Table 2. Summary of the physical properties, including the defect volume ratio, relative density, compressive strength, elastic
modulus, and hardness of the sintered SHPS120m, RCS120m specimens, and MW120m.

Sintered sample Defect volume ratio Relative density Compressive strength Young’s modulus
(%) (%) (MPa) (GPa)
SHPS120m 3.86 98.36 ± 0.54 158.35 ± 19.76 3.14 ± 0.04
MW120m 7.22 96.95 ± 0.48 86.62 ± 8.2 2.61 ± 0.21
RCS120m 4.64 95.02 ± 0.61 36.35 ± 0.26 2.45 ± 0.07
CS120m 16.13 93.49 ± 0.35 18.96 ± 2.66 1.08 ± 0.05

Volume 10 Issue 5 (2024) 374 doi: 10.36922/ijb.3609