热处理的选择性激光化合金 (Ti6Al4V) 陀螺圆柱体的静态压缩和疲劳行为
Sydney Hitchon1, William Anderson1, Jaques S Milner2
1School of Biomedical Engineering, Western University, London, Ontario, Canada; Bone and Joint Institute, Western University, London, Ontario, Canada.
Journal of the mechanical behavior of biomedical materials
|August 20, 2023
概括
增材制造创造了用于骨科的多孔植入物. 有限元 (FE) 建模准确预测机械行为,但疲劳寿命预测需要进一步校准以提高准确性.
科学领域:
- 生物材料工程 生物材料工程
- 机械工程 机械工程
- 整形外科手术 整形外科手术
背景情况:
- 多孔的增材制造结构为骨科植入物提供了潜力,减少压力屏蔽和增强骨内生长.
- 计算机辅助设计和有限元 (FE) 建模对于设计这些多孔生物医学植入物至关重要.
- 对于FE模型来说,对静态和疲劳行为的实验验证是必不可少的.
研究的目的:
- 为了比较增材制造的螺旋结构的机械行为,具有不同的孔隙度.
- 为了验证有限元 (FE) 模型与实验数据对静态和疲劳性能进行验证.
- 评估FE建模在预测多孔植入物疲劳寿命方面的准确性.
主要方法:
- 添加剂制造具有受控孔隙的圆柱状回旋结构.
- 机械测试原型,以确定静态和疲劳性能.
- 开发和验证有限元 (FE) 模型以模拟机械反应.
主要成果:
- 测量和预测的孔隙度与弹性明显模量之间的关系之间观察到很强的一致性.
- 增加的孔隙性导致疲劳寿命减少,当结构负载在相同的百分比的收益强度时.
- 疲劳强度系数的校准显著提高了FE模型的准确性,尽管仍然存在高达54%的差异.
结论:
- 有限元 (FE) 建模显示,有望帮助设计多孔骨科植入物.
- 需要进一步校准和验证,以完善FE模型中的疲劳寿命预测.
- 通过预测机械行为,FE建模可以指导多孔假肢的设计.
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