温度和湿度合对碳纤维复合材料/结合的衰老失败的影响
Han Peng1, Tai Zhou1, Linjian Shangguan1
1School of Mechanical Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450045, China.
Polymers
|April 13, 2024
概括
热量和湿度的组合显著影响结合关节的耐用性. 研究表明,增长的老化时间和环境水分含量降低了机械性能,同时也导致了结构粘合剂故障模式的转变.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 粘附科学 粘附科学 粘附科学
背景情况:
- 温度和湿度等环境因素显著影响结合关节的性能.
- 关于温度和湿度对结构粘合剂接头的结合作用的研究有限.
- 了解这些影响对于预测结合结构的长期耐用性至关重要.
研究的目的:
- 为了研究温度和湿度的老化对结构粘合剂结合的故障性能的影响.
- 分析吸水行为及其与机械性能降解的相关性.
- 确定衰老对故障模式的影响,并为生命设计提供见解.
主要方法:
- 在各种温度 (40°C,60°C) 和湿度 (95%,100%) 条件下,在较长时间 (240h,480h,720h) 的时间内,对粘接接头进行实验老化.
- 序列双Fick的模型来分析水吸收动力学.
- 准静态拉力试验用于评估机械性能 (强度,能量吸收).
- 里埃红外光谱学和扫描电子显微镜 (SEM) 用于材料分析和故障模式调查.
主要成果:
- 粘合剂的吸水率遵循了菲克定律.
- 机械性能降低与环境水分含量呈正相关.
- 温度后固化和水性塑性化的竞争机制导致故障强度和能量吸收略有增加.
- 故障模式随着老化时间的增加而从凝聚性转移到接口,这得到了SEM分析的证实.
结论:
- 温度和湿度的组合显著影响粘合关节的特性,而水分含量是减少性质的关键因素.
- 衰老引起的故障模式的变化对于理解关节退化至关重要.
- 结果为汽车应用中的粘接接头的可靠性和寿命设计提供了必要的数据.
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