在不同的负载条件下,绳-复合材料的疲劳行为
Julian Torggler1, Martin Leitner1, Christian Buzzi1
1Institute of Structural Durability and Railway Technology, Graz University of Technology, Inffeldgasse 25/D, 8010 Graz, Austria.
Materials (Basel, Switzerland)
|October 16, 2024
概括
较高的拉伸比率显著延长了绳-复合材料的使用寿命. 这项研究强调了在对这些材料的疲劳分析中考虑延展比的重要性.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 聚合物科学 聚合物科学
背景情况:
- 绳-复合材料在众多应用中至关重要,但它们的疲劳行为尚未完全理解.
- 疲劳是循环负荷下复合材料的关键故障机制.
研究的目的:
- 调查不同拉伸比对线索-复合材料疲劳寿命的影响.
- 为了比较纯脉冲拉伸应变下的疲劳性能与增加的平均应变条件下的疲劳性能.
主要方法:
- 开发具有代表性的绳索-复合物标本.
- 用一个验证的数值模型来评估疲劳参数.
- 进行循环疲劳测试,使用不同的应变比 (R ~0和0.2-0.3).
主要成果:
- 较高的拉伸比率 (0.2-0.3) 与纯脉冲拉伸式拉伸比率 (R ~ 0) 相比,显著增加了使用寿命.
- 斜率 (k) 从13增加到23,最终纤维拉伸率在50,000个周期内从8%增加到11%,以获得更高的拉伸比率.
- 两种测试系列都显示了可比的结果分散,表明一致的变化.
结论:
- 应变比是影响绳-复合材料疲劳行为的关键因素.
- 使用这些材料的组件的设计和评估必须考虑到不同的负载条件及其对疲劳寿命的影响.
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