摘要
背景:关节软骨一旦出现裂纹缺损其力学性能会发生改变,而先前研究中针对受损关节软骨的探究多集中在压缩,对于拉伸性能的研究较少。目的:预先在软骨层试样上制造裂纹缺损,测试其单轴准静态拉伸性能。方法:选取新鲜成年猪膝关节的关节软骨,制备含裂纹缺损的软骨试样,在不同应力率下(0.001,0.01,和0.1 MPa/s)测试其拉伸性能,在不同恒定应力下(1,2,3 MPa)测试其蠕变性能。结果与结论:①不同应力速率下的拉伸实验中,随着应力速率的增加,达到相同应变所需的应力逐渐增大,且试件的杨氏模量随应力率的增加而增加;②不同应力速率下含裂纹缺损关节软骨的拉伸应力-应变曲线不重合,说明含裂纹缺损关节软骨的拉伸性能具有率相关性;③不同恒定拉应力水平下的蠕变实验中,蠕变应变随着拉应力水平的提高而增大,蠕变柔量随拉应力水平的提高而降低,并且随着蠕变时间的推移蠕变应变先快速增加后缓慢增加;④结果表明,不同应力率和不同恒定应力对含裂纹缺损关节软骨的拉伸力学性能影响较大,该实验结果可为缺损关节软骨的修复提供力学参考。
BACKGROUND:Once the articular cartilage has a crack defect,its mechanical properties will change.In previous studies,the investigation of damaged articular cartilage mostly focused on compression,and there were few studies on tensile properties.OBJECTIVE:To measure the uniaxial quasi-static tensile properties by preparing crack defects on the cartilage layer samples.METHODS:The articular cartilage of the fresh adult pig knee joint was selected to prepare a cartilage specimen containing a crack defect.The tensile properties were tested at different stress rates(0.001,0.01 and 0.1 MPa/s)and the creep properties were tested under different constant stresses(1,2 and 3 MPa).RESULTS AND CONCLUSION:(1)In the tensile test at different stress rates,as the stress rate increases,the stress required to reach the same strain increased gradually,and the Young’s modulus of the test piece increases with the increase of the stress rate.(2)The tensile stress-strain curves of the articular cartilage with cracks at different stress rates did not coincide,indicating that the tensile properties of the articular cartilage with crack defects are rate-dependent.(3)In the creep experiment under different constant tensile stress levels,the creep strain increased with the increase of the tensile stress level,the creep compliance decreased with the increase of the tensile stress level,and with the creep time.The creep strain increased rapidly and then increased slowly.(4)To conclude,different stress rates and different constant stresses have great influence on the tensile mechanical properties of articular cartilage with crack defects.The experimental results provide a mechanical reference for the repair of defective articular cartilage.
作者
司雲朋
高丽兰
张春秋
彭宇霖
Si Yunpeng;Gao Lilan;Zhang Chunqiu;Peng Yulin(Key Laboratory of Advanced Electromechanical System Design and Intelligent Control,Tianjin University of Technology,Tianjin 300384,China;National Experimental Teaching Demonstration Center of Mechatronics Engineering,Tianjin University of Technology,Tianjin 300384,China;the Second Etching Division,Beijing North Huachuang Microelectronics Equipment Co.,Ltd.,Beijing 100176,China)
出处
《中国组织工程研究》
CAS
北大核心
2020年第2期187-191,共5页
Chinese Journal of Tissue Engineering Research
基金
国家自然科学基金项目(11572222),项目负责人:高丽兰
国家自然科学基金项目(11672208),项目负责人:张春秋
天津市自然科学基金重点项目(18JCZDJC36100),项目负责人:张春秋~~
关键词
裂纹缺损
关节软骨
单轴拉伸
应力速率
恒定应力
蠕变
生物力学
组织工程
crack defect
articular cartilage
uniaxial stretching
stress rate
constant stress
creep
biomechanics
tissue engineering
