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Dee, et al.
with a polymer having good interfacial strength with macro-porosity will be tuned by computer-aided design
CaP. Based on the tension-shear chain model, the ceramic (CAD) to study the influence of the CaP microstructure
composite is expected to absorb energy as the polymer design on the mechanical properties of the infiltrated
deforms until eventual platelet pull-out . CaP composites.
[3]
In addition, microstructure design is often used
to toughen such ceramic composites. The periodic Acknowledgments
orientation of microplatelets in the printed multi-layered The authors thank Chan Xin Ying for customizing the 3D
CaP (Figure 8F) bears resemblance to the periodic printer. The authors would like to acknowledge the Facility
structures in highly tough natural materials often employed for Analysis, Characterisation, Testing and Simulation,
in biomimetic materials for toughness enhancement, such Nanyang Technological University, Singapore, for use of
as the Bouligand structure . We indeed found that the their electron microscopy and X-ray facilities.
[46]
graded orientation of the microplatelets was effective
and driving the crack along curved path, following Funding
the orientation of the planes of the microplatelets (see
Supplementary File: Section 5 for images of an unusual, This work was supported by the National Research
curved crack path). Foundation, Singapore, with the Fellowship NRFF12-
2020-0006.
4. Conclusion Conflict of interest
In this paper, we have developed an ink composition
and 3D printing strategy to build complex shaped The authors declare no conflict of interest.
microstructured CaP-based materials. Aqueous inks Author contributions
containing CaP microplatelets were developed and
their rheology studied. These inks were being dried D.P. and T.S. prepared the samples. T.S. performed
upon deposition onto gypsum while simultaneously experiments and SEM imaging. D.P. analyzed the data
extruding the structure. We found that a concentration and drafted the manuscript. L.F.H. supervised the project,
of 21 – 24 vol% CaP microplatelets was optimum for designed the experiments, and reviewed the manuscript
printing and studied the microstructure obtained in
single filaments after calcination. In each filament, a References
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