Page 378 - IJB-10-5

International Journal of Bioprinting Tunable anisotropic gyroid bioscaffolds

structure in the 3D-printed specimens after curing. The densification and the formation of a crystal structure in the
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lamellar structure generally disappears after the post- ceramic cube specimens. The SMWH process promotes
thermal treatment and formed dense ceramic parts. As formation of cristobalite crystal structure in the ceramic
a result, after the debinding and sintering process, the cube specimen and facilitates densification, reducing the
3D-printed structures experience larger shrinkage in the H energy barrier for sintering compared to conventional
dimension. However, this phenomenon was not observed furnace heating. As a result, density of the specimens
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in the specimens prepared through the CS process. This closely approximates to the theoretical density value of 2.2
is likely due to the incomplete debinding due to the high g/cm for amorphous SiO due to the higher theoretical
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heating rate, which adversely affects the densification of density value of the cristobalite structure in SiO than the
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the specimens. amorphous form. On the other hand, specimens prepared
The relative density of the specimens was also through conventional heating exhibit lower relative
compared, as shown in Figure 4c. When subjected to the density, primarily due to the fast heating rate and short
same heating profile, the specimens fabricated through sintering time employed. These conditions may lead to the
the SMWH process exhibited higher relative densities incomplete removal of the organic binders before reaching
compared to those from the CS process. The relative the sintering temperature. As a result, the SiO particles are
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density of the MW specimens ranged from 95.38% to loosely in contact with each other, impeding the diffusion
97.4%, while the CS specimens showed values ranging process during sintering. The SMWH process shows
from 91.89% to 93.49%. These findings suggest that the a promising result in achieving higher relative density
SMWH process plays a significant role in promoting compared to the conventional furnace heating, indicating

Figure 4. Comparative analysis of 3D-printed ceramic cubes. (a) X-ray diffraction (XRD) pattern for the 3D-printed ceramic cube specimens. (b)
Dimensional shrinkage for the ceramic cube specimens processed through susceptor-assisted microwave heating (SMWH) and conventional furnace
heating. L, W, and H correspond to the length, width, and height of the specimens, respectively. (c) The effect of the dwell time of sintering on the relative
density of the specimens with respect to the theoretical density of amorphous SiO . The 3D reconstructed image obtained through micro-computed
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tomography (µ-CT) showing the defect distribution in the (d) CS120m and (e) MW120m specimens.

Volume 10 Issue 5 (2024) 370 doi: 10.36922/ijb.3609