Simulation Study on the Influence of Surface Curvature on the Mechanical Performance of Triply Periodic Minimal Surface Scaffolds

The mechanical properties of the porous biomimetic scaffolds need to closely match those of the defective tissue. Triply periodic minimal surface (TPMS) have gained widespread application in tissue engineering because of their smooth surface transition and low stress concentration. It is worth noting that the influence mechanism of surface curvature on the mechanical properties of these scaffolds remains unclear. In this paper, two typical TPMS lattices are selected to construct structures with identical porosity but varying surface curvatures, and the influence mechanism of surface curvature on the mechanical properties of the scaffolds is revealed based on finite element analysis (FEA). At the same time, the intrinsic relationship between porosity and surface curvature is also discussed. The results show that for structures with the same porosity, a more concentrated surface curvature distribution correlates with enhanced mechanical properties. Taking the structure with porosity of 55% as an example, the elastic modulus of the I-WPT structure is 1.37 times that of the I-WP structure, and the elastic modulus of the GT structure is 1.38 times that of the G structure. Changes in porosity impact the surface curvature distribution, with higher porosity leading to a more dispersed curvature distribution, which can easily lead to stress concentration of the structure and weaken its bearing capacity. For different types of lattices, mechanical properties are less sensitive to surface curvature than macroscopic geometric features.