手术生长棒中的残余应力
Maïté Croonenborghs1, Karim Ismail1, Maryline Mousny2
1Institute of Mechanics, Materials and Civil Engineering, Université catholique de Louvain, Place Sainte Barbe 2 L5.02.02, Louvain-la-Neuve 1348, Belgium.
Journal of biomechanical engineering
|October 13, 2023
概括
改善手术生长棒的早期脊椎病症包括提高疲劳抵抗力. 压缩残余应力,特别是在射击切割和曲后,是增加这些医疗器械寿命的关键.
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:
- 对于早期发生的脊椎结节病,手术生长棒的失败率很高.
- 通过诱导压缩残余应力,可以增强耐疲劳性.
- 了解残留应激演变对于改善植入物寿命至关重要.
研究的目的:
- 为了研究Ti-6Al-4V生长棒中的残余应力概况的演变.
- 为了将材料特性和加工步骤与剩余应力产生相关联.
- 为延长生长棒的寿命提供指导方针.
主要方法:
- 通过聚焦离子束 (FIB) 进行微光束环芯研磨的数字图像相关性 (DIC) 用于残余应力评估.
- 在曲之前和之后,对射击磨的杆子获得了实验应力概况.
- 一个有限元模型 (FEM) 被开发并与实验数据验证.
主要成果:
- 在曲后,压缩残余应力保持在杆子的形和形两侧.
- 最初的射击压缩和背压的组合显著影响了表面压缩应力产生.
- 参数分析确定了初始度强度和动力硬化作为主要因素,曲角度和射击深度不那么重要.
结论:
- 具有高动力硬化和低性强度的材料是诱导压力余应力的最佳材料.
- 优化射击切割强度和材料特性可以提高生长棒的疲劳抵抗力.
- 这项研究为设计更耐用的生长棒提供了基础,降低了脊椎病治疗失败率.
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