跨CFRP层材中疲劳损伤的数值模拟:探索频率依赖和内部热生成效应
Natsuko Kudo1, M J Mohammad Fikry2, Shinji Ogihara3
1Department of Materials Science and Technology, Graduate School of Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan.
Polymers
|February 13, 2025
概括
碳纤维增强塑料 (CFRP) 的疲劳损伤取决于测试频率. 高频加速由于热量积累而造成的损伤,而低频表现出明显的粘弹性效应,影响裂纹形成周期.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 计算力学 计算力学 计算力学
背景情况:
- 碳纤维增强塑料 (CFRPs) 的疲劳损伤是结构完整性的关键问题.
- 了解加载频率对疲劳裂启动和传播的影响,对于材料设计和性能预测至关重要.
研究的目的:
- 在CFRPs中数值调查疲劳损伤进展的频率依赖.
- 在各种疲劳测试频率下模拟裂的启动和传播.
- 分析频率依赖损害积累的潜在机制.
主要方法:
- 使用增强的可降解的哈辛故障模型进行数值模拟.
- 在0.1Hz,1Hz和10Hz的循环负荷下模拟横向裂纹启动和传播.
- 员工调整了数值,以加快损坏的分析.
主要成果:
- 对于0.1 Hz (174 个周期),1 Hz (209 个周期) 和10 Hz (165 个周期) 的裂纹形成周期的模拟结果与实验观察结果一致.
- 证明高频负载导致内部热量产生超过散热,加速损坏.
- 观察到低频负载增强粘弹性散射,影响到达到损伤状态的循环数.
结论:
- 在CFRP中,疲劳损伤积累率最初会随着测试频率的增加而增加,但随后会下降.
- 高频的内部热量产生和低频的粘弹性消散是影响频率依赖性疲劳损伤的关键因素.
- 这些发现对于评估现实世界CFRP结构部件的疲劳损伤至关重要.
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