收缩表面地形对接触变形和应力的影响
R A Diaz-Lopez1, P H Wen1, J C Shelton1
1School of Engineering and Materials Science, Queen Mary University of London, UK.
Journal of the mechanical behavior of biomedical materials
|November 12, 2023
概括
精确建模全关节置换术的缩表面至关重要. 现实的表面地形,而不是简化的模型,准确地预测了部植入物中的接触力学和潜在的故障风险.
科学领域:
- 生物材料工程 生物材料工程
- 整形植入物设计 整形植入物设计
- 表面计量学 表面计量学
背景情况:
- 结症是关节整体置换中的一个失败模式,与线接口问题有关.
- 当前的计算模型往往过于简化了圆表面的地形,可能误解了接触力学.
- 制造商设计的变化凸显出需要更深入地了解圆表面相互作用的必要性.
研究的目的:
- 测试假设,简化的几何函数可以预测组装的圆的表面力学.
- 为了研究测量钻孔和杆表面地形对形接触力学的影响.
- 在有限元分析中,比较简化与现实的表面模型的预测准确度.
主要方法:
- 用粗度参数和光谱密度来测量和模拟钻孔和杆表面的表征.
- 开发2D有限元 (FE) 模型,结合CoCr合金腿部头部和Ti合金子的特征表面形状.
- 模拟组装条件在变化的结果力 (0.54.0 kN) 下,以确定接触条件和塑料应变.
主要成果:
- 测量到的圆面显示出多达七个主要的空间频率,与简化模型不同.
- 组装会导致杆微顶的平坦化,与理想表面相比,减少接触点.
- 简化的直线和正弦波函数高估了接触点,而现实的地形学揭示了接触点的高塑性应变.
结论:
- 简化的几何函数不足以准确预测部整体关节置换中的凸接触力学.
- 纳入测量,复杂的表面地形是必要的,以实现逼真的模拟的形接口行为.
- 表面变化显著影响缩性能,影响潜在的纹,腐蚀和植入物的寿命.
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