Structural Investigation of Delicate-Geometry Fused Deposition Modeling Additive Manufacturing Scaffolds: Experiment and Analytics

Additive manufacturing is a rapidly expanding technology in many scientific fields like tissue engineering. One of the most essential duties of tissue engineering scaffolds is to provide sufficient mechanical strength for the injured bone tissue. Scaffold architecture plays a significant role in its mechanical properties. Here, six delicate different geometry computer-aided design models with identical porosity were designed. The sets of 0/90, 0/45/135/90, 0/60/120, and their shifted models as the most prevalent scaffold geometries were fabricated by fused deposition modeling printer through the optimized processing parameters and were investigated by the upset test. Their modified models according to printing procedure changes were redesigned, and finite element analysis (FEA) simulations were accomplished through a simplifying strategy. Mechanical performances of the designed scaffolds were evaluated, and a good agreement was observed between the FEA and experiments. The strongest patterns were derived via evaluation of three aspects of scaffold elastic modulus, scaffold yield strength, and a newly defined parameter named “scaffold geometry rupture resistance factor”. The large difference between Young's modulus of 0/90 (230.44 MPa) and 0/90 shifted (156.56 MPa) indicated the role of scaffold geometry in mechanical properties. The mechanical effect of layer pattern sequence change was also investigated.