非自相似分层次结构对骨组织断裂力学性能分析  

Effects of Non-Self-Similar Hierarchy on Fracture Mechanical Properties of Bone

作　　者：李兴国 安兵兵[2,3] 张东升[2,3] 樊艳红 常超 LI Xingguo;AN Bingbing;ZHANG Dongsheng;FAN Yanhong;CHANG Chao(School of Applied Sciences,Taiyuan University of Science and Technology,Taiyuan 030024,China;School of Mechanics and Engineering Science,Shanghai University,Shanghai 200444,China;Shanghai Institute of Applied Mathematics and Mechanics,Shanghai 200444,China)

机构地区：[1]太原科技大学应用科学学院,太原030024 [2]上海大学力学与工程科学学院,上海200444 [3]上海市应用数学和力学研究所,上海200444

出　　处：《医用生物力学》2021年第1期30-35,共6页Journal of Medical Biomechanics

基　　金：国家自然科学基金项目(11802194,11772184);山西省青年科技研究基金项目(201801D221018)。

摘　　要：目的研究非自相似分层次结构对生物复合材料的断裂力学性质及裂纹在其中扩展的影响。方法利用ABAQUS软件进行建模,采用扩展有限元法分别模拟矿物晶体长轴方向与矿化胶原纤维长轴方向夹角θ=0°、20°、40°、60°、80°时矿化胶原纤维束的刚度以及裂纹在其中产生和扩展情况。结果当θ≤40°时,θ对材料刚度的影响很小;当θ>40°时,材料刚度随着θ增大而减小,其极限拉伸应变随着θ增大而增大。当θ>0°时,裂纹在增强项两侧蛋白质扩展过程中有不对称现象,矿物晶体长轴偏转的一侧裂纹相对更容易扩展。结论生物硬组织材料中的非自相似分层次结构使得材料中的裂纹分布变得不均匀,故硬组织材料中的非一致排列现象可使得材料在外载荷作用下发生局部破坏而非灾难性脆断。研究结果可为材料设计提供理论支持。Objective To study the effect of non-self-similar hierarchy on fracture mechanical properties and crack propagation of the biocomposite. Methods The numerical models were established by using ABAQUS,and the stiffness and crack initiation and propagation in the biocomposite with the inclination angles between the axis of the prism and mineralized collagen fibrils θ = 0°,20°,40°,60°,80° were simulated by extended finite element method. Results The inclination angle θ had limited influences on biocomposite stiffness at θ ≤ 40°,while biocomposite stiffness decreased with θ at θ >40°. The ultimate tensile strain also increased at θ >40°. Asymmetry in the crack was also found during propagation of matrix surrounded-enhanced phases at θ > 0°. The crack propagatation on one side of the long axis of the mineral crystal was relatively easier than that on the other side atθ >0°. Conclusions The non-uniform distributions of cracks were found in biological hard tissues arisen from the non-self-similar hierarchy. The non-uniform crystal arrangement in the biocomposite would result in local damage rather than catastrophic fracture. The findings of this study can provide theoretical support for material design.

关 键 词：骨 扩展有限元 裂纹扩展 

分 类 号：R318.01[医药卫生—生物医学工程]