Biomimetic Design and Performance of TPMS Radial Continuous Gradient Porous Bone Scaffolds

In this study, radial pore continuous gradient porous bone scaffolds were designed and optimized based on the Gyroid single-cell structure to meet the demand for high-performance bone implants in bone tissue engineering. Ti–6Al–4V alloy scaffolds with varying single-cell sizes and porosities were fabricated using laser powder bed fusion (PBF-LB) technology for comparative analysis. The findings revealed that the radial pore continuous gradient porous structure exhibited superior mechanical properties and permeability, coupled with a large specific surface area and a helical trajectory for fluid permeation. These features significantly enhanced cell attachment and promoted bone regeneration. The mechanical properties of the scaffolds were further refined, and their toughness was improved through heat treatment of the Ti–6Al–4V alloy. Among the tested designs, the G3-60 scaffold demonstrated the most balanced performance, achieving an elastic modulus of 8.23 GPa, a yield strength of 300.09 MPa, a maximum specific surface area of 3559.362 mm², and a permeability of 2.984 × 10⁻³m² at a flow velocity of 0.1 mm/s. This scaffold not only provides exceptional mechanical load-bearing capacity and permeability but also offers a substantial surface area to support osteoblast attachment and proliferation. These results provide critical theoretical insights and technical guidance for the future design and clinical application of advanced bone implants.

Graphical Abstract