相关实验视频
Updated: Jun 23, 2025

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Ultrasonic Fatigue Testing in the Tension-Compression Mode
Published on: March 7, 2018
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在随机和恒定幅度疲劳负荷下复合螺栓连接的疲劳分析
Song Zhou1, Bo Yang2, Yichang Huang2
1College of Civil Aviation, Northwest Polytechnical University, Taicang 215400, China.
Materials (Basel, Switzerland)
|June 19, 2024
概括
本研究使用两种方法分析关节的随机疲劳寿命和故障模式:线性累积损伤和等效负荷有限元分析. 这两种方法都准确地预测了实验疲劳的结果,其因数为2.
科学领域:
- 机械工程 机械工程
- 材料科学 材料科学 材料科学
- 结构完整性 结构完整性
背景情况:
- 关节是许多结构中的关键组件,在随机负荷下,它们的疲劳寿命对于安全性和可靠性至关重要.
- 在复杂的随机负载下预测关节的疲劳寿命和故障模式仍然是一个重大的工程挑战.
研究的目的:
- 分析关节的随机疲劳寿命和故障模式.
- 为了比较预测随机疲劳寿命的两个不同的计算方法的准确性.
主要方法:
- 对四种关节设计进行了静态,恒定振幅疲劳和随机疲劳测试.
- 采用线性累积损伤方法,将疲劳寿命与负载幅度和分布联系起来.
- 使用等效负载有限元方法来建模刚度/强度降解,并预测随机疲劳寿命.
主要成果:
- 线性累积损伤和等效负荷有限元素方法都与实验疲劳数据有很好的一致性.
- 所有预测结果都落在从实验结果的两倍分散带内.
- 这项研究成功地模拟了同等的随机生命和疲劳失败模式.
结论:
- 线性累积损伤和等效负荷有限元方法对于预测关节的随机疲劳寿命和故障模式是有效的.
- 经过验证的方法为在随机操作条件下评估接头的结构完整性提供了可靠的工具.
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