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Ultrasonic Fatigue Testing in the Tension-Compression Mode
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在轴向和曲超声波疲劳负荷下对正极聚合物复合材料的应力和应变计算方法
Aravind Premanand1, Frank Balle2
1Department for Sustainable Systems Engineering (INATECH), Faculty of Engineering, University of Freiburg, Germany.
Ultrasonics
|August 18, 2023
概括
超声波疲劳测试可以加速复合材料的评估. 这项研究使用激光多普勒振动计和有限元素分析成功确定了碳纤维增强聚合物复合材料的循环应力.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 复合材料 复合材料 复合材料
背景情况:
- 加速疲劳测试对于有效评估复合材料的非常高循环疲劳行为至关重要.
- 超声波疲劳测试提供了一种方法,可以在20kHz进行高达10^9周期的实验,比传统方法 (5-50Hz) 快得多.
- 在超声波加载条件下准确确定周期应力是一个重大挑战.
研究的目的:
- 为了研究和确定超声波疲劳负荷期间的循环应力.
- 为了评估碳纤维5H布增强在聚乙基基 (CF-PEKK) 复合材料的疲劳行为.
- 通过计算模型对实验方法进行验证.
主要方法:
- 在单轴和三点曲条件下开发了两种用于超声波测试的实验设置.
- 使用3D扫描激光多普勒振动计 (3D-SLDV) 和单点激光多普勒振动计 (LDV) 来测量样品位移.
- 在弹性负载条件下计算的应变和应力,基于位移测量.
- 使用有限元模型与实验结果进行比较.
主要成果:
- 在超声波循环加载期间成功测量了CF-PEKK样本的振荡位移.
- 在弹性负载条件下计算的结果应变和应力.
- 实验结果与有限元模型预测有很好的一致性.
- 证明了拟议的超声波疲劳测试方法的可行性.
结论:
- 开发的超声波疲劳测试方法,集成激光多普勒振动计和有限元分析,准确地确定CF-PEKK复合材料中的循环应力.
- 这种方法提供了一种可靠和有效的方法来评估复合材料的非常高循环疲劳行为.
- 这些发现支持超声波疲劳测试在材料科学和工程中的更广泛应用.
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