摘要
目的采用有限元分析法测试记忆合金节段内固定器的抗拉强度及其在加载时的应力分布。方法将节段内固定器的设计参数、实体扫描图象及材料力学特性输入计算机,在ANSYS软件固有的三维坐标系中建立节段内固定器的实体模型,并进行网格划分,然后给予拉伸载荷,测量承载点的拉力及内固定器的应力分布。结果当节段内固定器两钩中点被拉开2 mm时,承载点的拉力为281 N,应力分布在内固定器的中间部位最集中,在两钩部较小。结论节段内固定器抗拉能力强,固定牢固,内固定器的中间部是加载时应力最集中的部位,是最易发生疲劳、断裂的部位。
Objective To study the tensile strength of shape memory alloy intrasegmental fixator and tensile stress distribution in the device during force loading with finite element method (FEM). Methods The designed parameters, scanning image, and mechanical properties of shape memory alloy intrasegmental fixator were input into computer for the construction of the FEM model of the device in inherent coordinate of ANSYS. The model was extended with restriction in different parts, and the tensile strength and the distribution of tensile stress in the model was calculated. Results When the device was loaded with pulling force to induce a relative displacement of 2 mm between the 2 hooks along the two midpoints, the pull was about 281 N, and the tensile stress concentrated more on the middle of device than on the two sides. Conclusions The shape memory alloy intrasegmental fixator is strong enough against tensile stress, which concentrates in the middle portion of the device where fatigue breakage is liable to occur when excessive force is loaded.
出处
《第一军医大学学报》
CSCD
北大核心
2002年第12期1128-1130,共3页
Journal of First Military Medical University
基金
广东省重点科技攻关项目(粤科字[1999]245)
关键词
腰椎峡部裂
记忆合金内固定器
生物力学
有限元分析
lumbar spondylolysis
internal fixator, memory alloy
biomechanics
finite element analysis
