Analysis of graded cellular solids in static and fatigue compression

Full description

Functionally graded structures are commonly found in nature, such as in bone and plants. Inspired by these biological systems, this study investigates how well theoretical predictions match experimental observations of functionally graded flexible scaffolds designed for applications in tissue engineering, specifically breast tissue regeneration. Specifically, functionally graded configurations of gyroid and rectilinear cellular solids with porosities of 90%, 94%, and 96% were 3D-printed using thermoplastic polyurethane, and their performance was compared to that of scaffolds with uniform porosity. These porosities were used to create 18 groups (n=5 per group) consisting of 2-graded and sandwich designs with different stacking sequences.

To evaluate the mechanical properties, the study thoroughly examined how graded gyroid and rectilinear samples deform under static and fatigue compression. Our results demonstrate that incorporating gradients into high-porosity cellular solids offers significant potential to tailor mechanical properties. In particular, graded designs enhance energy absorption at later stages of deformation while reducing stiffness, thereby offering improved tactile response for flexible biomedical applications.

The use of gradient gyroid architectures facilitates more efficient printing strategies without the need for support structures. This finding opens new opportunities for the development of second-generation implants in scaffold-guided breast tissue regeneration.