ADDITIVE MANUFACTURING FOR BONE LOAD BEARING APPLICATIONS - 3D Bioprinting and Nanotechnology in Tissue Engineering and Regenerative Medicine - page 243

FIGURE 11.6
Novel multiscale 3DP additive manufacturing system for fabrication of functionally graded porous structures. (100)
Granite support, (101) Precision xy gantry assembly, (102) Counter rotating roller module, (103) Multiple supply
bed selection and alignment module, (104) Binder dispensing print head module, (105) Build bed module, (106)
Sacrificial porogen particle insertion module, (107) Microsyringe sacrificial polymer deposition module, (108)
Microsyringe deposition control, (109) Precision control z -axis, (110) UV curing module.
thickness of 150 m m. The green parts were then sintered in a high-temperature furnace (Lindberg/Blue
M, ThermoScientific) with an established heat treatment protocol ( Pilliar et al., 2009 ).
Figure 11.8 a illustrates the compressive strength measurements plotted against porosity values,
with statistical significance derived from one-way ANOVA. The mechanical compression test results
were surprising. The category of samples with the highest compressive strength corresponded to parts
manufactured using the large powder size, with a compressive strength of 15.5 ± 1.9 MPa, the result
being corroborated by bulk density and bulk porosity measurements.
The literature suggests that samples with a lower particle size composition manufactured using 3DP
approaches would result in parts with a higher mechanical compressive strength ( Will et al., 2008 ). The
discrepancy between expected results and the actual results obtained in this chapter can be explained