承力骨支架微孔结构设计及力学特性有限元分析

Design and Finite Element Analysis of the Mechanical Properties of Cellular Structure of Human Load-Bearing Bone Scaffold

承力骨支架作为人体缺损骨的替代物,不仅支撑着人体的重量,而且承受着外来的冲击。根据天然骨骼的扫描电镜形貌特征,设计了三种骨骼内部微孔单胞模型。通过ADINA有限元分析软件,分析了给定压缩应变载荷条件下,模型载荷固定端总合力同应变的关系。研究了弹性模量和孔隙率随模型参数的分布及不同孔径尺寸和孔几何形状对单胞结构力学性能的影响。结果表明:经优化的三种单胞模型同人体承力骨弹性模量相匹配,且具有较高的孔隙率及良好的连通性,为后续植入人体承力骨支架的结构设计和快速成型制造奠定了基础。

As a substitute for defected bone of human body, load-bearing bone scaffold supports not only the weight, but also bears the external impact. According to the morphological characteristics of the scanning electron microscope of the natural bone, three types of basic unit cells were designed. Based on the ADINA finite element analysis software, the relationship between the total force of the fixed end and strain was analyzed under the given compression strain. Studied on the distribution of elastic modulus and porosity with the model parameters, as well as the effects of pore size and pore geometry on mechanical properties of basic unit cells. The results showed that the optimized cell models were matched with the elastic modus of human bone, and had high porosity and good connectivity, which also laid the fouudation for the structure design and rapid prototyping of the implanted bone scaffold.