检查商业高性能环氧矩阵的半静态单轴压缩行为
J F Gargiuli1, G Quino1,2, R Board1
1Bristol Composites Institute, School of Civil, Aerospace, and Design Engineering, Faculty of Science and Engineering, University of Bristol, Queen's Building, University Walk, Bristol BS8 1TR, UK.
Polymers
|October 14, 2023
概括
这项研究评估了用于航空航天应用的四种商业环氧树脂. 强化策略影响了压力应变-应变行为,一些提高了性能,而另一些则降低了产量后的性能.
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
- 机械工程 机械工程
背景情况:
- 航空航天应用需要高性能环氧矩阵,具有量身定制的机械性能.
- 了解硬化剂对压缩时环氧树脂行为的影响,对于材料选择至关重要.
研究的目的:
- 为了评估和比较四个商业芳香环氧基质矩阵的准静态单轴压缩行为.
- 研究不同硬化策略 (热塑,颗粒,组合) 对环氧树脂机械反应的影响.
- 为了将压缩数据与热分析 (DSC,TGA) 和聚合物结构相关联.
主要方法:
- 在四种商用环氧树脂 (CYCOM®890,CYCOM®977-2,PR520,PRISM EP2400) 的准静态单轴压缩测试中.
- 动态扫描热量测量 (DSC) 和热重力测量分析 (TGA) 用于热特性.
- 对应力-应变曲线,真轴应力和扩张角的分析.
主要成果:
- 与基线CYCOM®890.2相比,热塑性硬化CYCOM®977-2显示真轴应力增加.
- 颗粒硬化PR520经过度点后表现出降低的真轴应力.
- 在塑料区域,PRISM EP2400 (组合硬化) 的应力值与CYCOM®890相当.
- 扩展角接近0°,在0.3塑料应变时,表明与聚合物结构相关的变化.
- 商用树脂的压缩模量较高,但产量应力低于模型树脂.
结论:
- 硬化策略显著改变了航空航天环氧树脂的压缩行为.
- 在压力响应的特定方面,CYCOM®977-2和PRISM EP2400提供了性能优势.
- 商用环氧树脂提供高压缩模量,对结构完整性至关重要,但需要仔细考虑产量应力限制.
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