Page 286 - IJB-9-4

International Journal of Bioprinting 3D printing of continuous fiber reinforced PLA/PGA composites

Figure 7. (A) Stress–strain curves of specimens with different printing spacings and (B) tensile strengths of specimens with different printing spacings.
The tests were used to determine significant differences between groups (**p < 0.01, ****p < 0.0001; “•” represents the tensile test results of each specimen).

Figure 8. (A) Stress–strain curves of specimens with different printing speeds and (B) tensile strengths of specimens with different printing speeds. The
tests were used to determine significant differences between groups (“ns” indicates no significance; “•” represents the tensile test results of each specimen).

96.13 ± 8.09 MPa, decreasing by 117.7%. Figure 8 shows after fracture are shown in Figure 9. Figures 9A and B
the effect of the printing speed on the tensile strength. show the tensile curve and fractured specimen of scheme
The tensile strength did not exhibit a significant difference 3, which was printed with the maximum layer thickness
among the three printing speeds. (0.25 mm). The specimen fracture mode of scheme 3 was

The 3DFFSMS analysis was conducted to study the quite different from those of other specimens. After the
failure mode of the specimens during the tensile process. PLA matrix material was debonded from the PGA fibers,
The strain cloud is the strain distribution on the specimen continuous single fibers worked as the main component to
surface measured by 3DFFSMS. During the tensile test, the bear the tensile stress. No more data were collected by the
color and shape of the strain cloud change in real time, and 3DFFSMS after point IV on the stress–strain curve. As the
the red area represents the area with large strain. The strain tensile test continued, the internal fibers were gradually
clouds corresponding to the marked points on the stress– pulled off, and the printed layer was gradually debonded
strain curves of schemes 3, 4, and 6 and the specimens until the test stopped. It can be seen from Figure 9B that

Volume 9 Issue 4 (2023) 278 https://doi.org/10.18063/ijb.734