Mechanical and Fluid Characteristics of Triply Periodic Minimal Surface Bone Scaffolds under Various Functionally Graded Strategies

A laser powder bed fusion additive manufacturing has enabled the fabrication of Triply Periodic Minimal Surface (TPMS). These structures are widely acknowledged for their suitability in bone implant applications. Nevertheless, although it is essential for TPMS-based implants to exhibit graded features to mimic those of natural bones for desirable functionality, the effect of graded features on mechanical properties, flow behavior, and geometrical morphologies requires further clarification. As a result, the present study carried out a comprehensive numerical and experimental assessment on the impact of graded IWP structures on the effective elastic modulus, Gaussian curvature, permeability, and fluid-induced wall shear stress. Among various TPMS architectures, the IWP structure was chosen to be explored in this work owing to its favorable physical responses for bone tissue ingrowth as reported in the literature. Overall, we found that the grading features had a considerable impact on the global response such as the effective modulus and fluid permeability. However, the local response such as Gaussian curvatures and fluid-induced wall shear stress was significantly less affected.