Lv Yuting, Liu Guohao, Wang Binghao, Tang Yujin, Lin Zhengjie, Liu Jia, Wei Guijiang, Wang Liqiang
College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao, China.
State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai, China.
Front Bioeng Biotechnol. 2022 Jun 8;10:910475. doi: 10.3389/fbioe.2022.910475. eCollection 2022.
The pore strategy is one of the important factors affecting the biomedical porous scaffold at the same porosity. In this work, porous scaffolds were designed based on the triply periodic minimal surface (TPMS) structure under the same porosity and different pore strategies (pore size and size continuous gradient distribution) and were successfully prepared using a novel NiTiNb alloy and selective laser melting (SLM) technology. After that, the effects of the pore strategies on the microstructure, mechanical properties, and permeability of porous scaffolds were systematically investigated. The results showed that the NiTiNb scaffolds have a low elastic modulus (0.80-1.05 GPa) and a high ductility (15.3-19.1%) compared with previous works. The pore size has little effect on their mechanical properties, but increasing the pore size significantly improves the permeability due to the decrease in specific surfaces. The continuous gradient distribution of the pore size changes the material distribution of the scaffold, and the smaller porosity structure has a better load-bearing capacity and contributes primarily to the high compression strength. The local high porosity structure bears more fluid flow, which can improve the permeability of the overall scaffold. This work can provide theoretical guidance for the design of porous scaffolds.
孔隙策略是在相同孔隙率下影响生物医学多孔支架的重要因素之一。在这项工作中，基于三重周期极小曲面（TPMS）结构，在相同孔隙率和不同孔隙策略（孔径和尺寸连续梯度分布）下设计了多孔支架，并使用新型NiTiNb合金和选择性激光熔化（SLM）技术成功制备。之后，系统研究了孔隙策略对多孔支架微观结构、力学性能和渗透性的影响。结果表明，与先前的研究相比，NiTiNb支架具有较低的弹性模量（0.80 - 1.05 GPa）和较高的延展性（15.3 - 19.1%）。孔径对其力学性能影响较小，但由于比表面积减小，增大孔径会显著提高渗透性。孔径的连续梯度分布改变了支架的材料分布，较小孔隙率结构具有更好的承载能力，对高抗压强度起主要作用。局部高孔隙率结构承受更多的流体流动，可提高整个支架的渗透性。这项工作可为多孔支架的设计提供理论指导。
