在高温环境下浸泡在海水中的两个环氧粘合剂BFRP接头的耐用性
Ruitao Niu1, Yang Yang2, Zhen Liu3
1School of Aerospace Engineering, Zhengzhou University of Aeronautics, Zhengzhou 450046, China.
Polymers
|August 12, 2023
概括
在盐水中老化的基岩纤维增强聚合物 (BFRP) 接头由于吸水而降低了强度,Araldite®2011的性能优于Araldite®2014. 湿热效应降解了聚合物,改变了故障模式并削弱了键.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 海军建筑 海军建筑
背景情况:
- 纤维增强聚合物 (FRP) 为造船应用提供了巨大的潜力.
- 基岩纤维增强聚合物 (BFRP) 正因其经济和环境优势而受到关注.
- 了解BFRP接头在海洋条件下的长期耐用性至关重要.
研究的目的:
- 研究盐水环境中老化对BFRP单接头 (SLJ) 机械性能和故障机制的影响.
- 为了在模拟的海洋老化条件下比较两个不同的环氧粘合剂 (Araldite®2011和Araldite®2014) 的性能.
- 分析BFRP接头组件的吸水特性和降解行为.
主要方法:
- 对与Araldite®2011和Araldite®2014结合的BFRPSLJ进行实验分析,在3.5%和5%的NaCl溶液中在80°C下长达720小时老化.
- 使用顺序双Fickian (SDF) 模型进行水吸收建模.
- 使用差分扫描热量计 (DSC) 进行玻璃过渡温度 (Tg) 和热重量计分析 (TG) 进行热降解,对老化的粘合剂进行表征.
- 准静态拉伸试验用于评估关节强度和刚度.
- 使用扫描电子显微镜与能量分散式X射线光谱学 (SEM-EDX) 进行关节截面的显微镜分析.
主要成果:
- 吸水主要发生在粘合剂层中,Araldite®2011比Araldite®2014.4吸收更多的水.
- 在较高温度下在盐溶液中老化导致粘合剂的Tg下降,并且由于湿热效应而导致聚合物降解.
- 随着含水量增加,关节失效强度下降,与溶液度正相关.
- 与Araldite®2014相比,使用Araldite®2011的BFRP接头具有更好的机械性能和稳定性.
- 由于结合水的二次交联,观察到硬度略有增加.
- 故障模式从纤维撕裂转变为纤维撕裂和粘合剂凝聚力故障的组合,归因于粘合剂塑化和盐离子腐蚀.
结论:
- 潮湿热效应和盐离子腐蚀显著降低了BFRP接头,削弱了粘合键并改变了故障机制.
- 与BFRP SLJs的Araldite®2014相比,Araldite®2011在盐水环境中显示出更好的耐用性和机械稳定性.
- 粘合剂层的吸水是影响BFRP接头在海洋应用中的长期性能的一个关键因素.
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