在单向纤维增强聚合物中通过小块样本的离轴压缩对故障行为进行表征
Fan Yang1, Yazhi Li1, Biao Li1
1Department of Aeronautical Structural Engineering, School of Aeronautics, Northwestern Polytechnical University, Xi'an 710072, China.
Polymers
|December 23, 2023
概括
这项研究调查了复杂负载下的复合材料故障,发现动作平面标准对矩阵故障有效,但对于光纤故障不那么有效. 精细化改进了纤维增强聚合物的预测.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 聚合物科学 聚合物科学
背景情况:
- 单向纤维增强聚合物 (FRP) 在先进的工程应用中至关重要.
- 了解它们在联合负载下失效机制对于安全设计至关重要.
- 轴外负荷引入复杂的应力状态,挑战现有的预测模型.
研究的目的:
- 实验性地研究单向FRP在纵横压缩和平面内剪切的情况下的故障行为.
- 为了比较分析四个突出的失败理论 (哈辛,卡曼霍,帕克,LaRC05) 的预测能力.
- 评估行动平面标准和纤维曲理论在预测复合材料故障模式方面的有效性.
主要方法:
- 用十种不同纤维方向 (0°至90°) 的块状,末端装载样本进行实验测试.
- 应用专门的固定装置来诱导组合负载并实现最终故障.
- 对实验结果与Hashin,Camanho,Puck和LaRC05失败理论的预测进行比较分析.
- 对矩阵和纤维主导故障模式的动作平面标准和纤维扭曲理论的评估.
主要成果:
- 识别了不同的故障模式,包括纵向压缩,内平面剪切和横向压缩.
- 行动平面标准在预测矩阵主导的故障方面表现优异,包括应力和断裂导向.
- 现有的理论在准确预测纤维占主导地位的故障方面存在局限性,特别是剪切对纤维压缩的影响.
- 纤维曲理论为曲带形成提供了合理的解释,但产生了保守的预测.
- 基于实验数据的理论重新校准和改进提高了预测准确性.
结论:
- 离轴压缩试验对于表征单向复合材料的复杂故障行为至关重要.
- 行动平面标准为FRP中矩阵主导的故障预测提供了一个强大的框架.
- 需要进一步开发以准确模拟纤维主导的故障,特别是在剪切影响下.
- 实验验证和理论改进是推进复合故障分析的关键.
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