Abstract：The aim of this work is to investigate the optimized analysis on the femur finite element model in the distribution gradient of material attributes, getting the precise and economic divided layers, which can be used as the theoretical support for the application of CT gray value assignment in the research area of medical finite element. The femur of an adult volunteer was firstly selected for CT scanning, the obtained DICOM format CT serial medicinal image data were input into Mimics, and the 3D rendering model was constructed. On this basis, using SolidWorks to substantiate the model, importing it into HyperMesh for volume mesh division, and then returning to Mimics, choosing layer 2, 4, 5, 10, 50, 100, 200 and 400 eight kinds of the gradient for material assignment. Finally, the working condition of the finite element model was set in ABAQUS software for simulation analysis. At the same time, the femur proxima finite element was established, and its validity was verified through the comparative analysis with literature data. Results showed that the level of stress and strain of the established femur finite element model had similar results with the experimental results in the literature; thus the effectiveness of the femoral finite element model was fully verified. The optimized analysis on the distribution gradient of material attributes: compared with the material properties of other layers, the stress of layer 2, 4, 5 and 400 was significantly different (P<0.05), and the stress between the four groups of material properties was significantly different (P<0.05),while the stress results of layer 10, 50, 100 and 200 were not significantly different. The material properties of the finite element model should be divided in an appropriate way. We found out that the material properties in 10 layers could not only improve the calculation speed and save the calculation amount, but also ensure the accuracy of the calculation results; the CT gray value assignment could be used to the analysis on the clinical individualized rapid finite element simulation.
金乾坤, 王巍, 何盛为, 何飞熊, 陈秉智, 傅彦棉. 股骨有限元模型材料属性分配梯度的优化分析[J]. 中国生物医学工程学报, 2020, 39(1): 84-90.
Jin Qiankun, Wang Wei, He Shengwei, He Feixiong, Chen Bingzhi, Fu Yanmian. The Optimized Analysis on the Distribution Gradient of Material Attributes of Femur Finite Element Model. Chinese Journal of Biomedical Engineering, 2020, 39(1): 84-90.
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