对非线性时间依赖构成模型的性能进行比较,这些模型是用最小的测试数据对环氧树脂进行校准的
Rui Miranda Guedes1,2, José Lopes Morais3
1LAETA-Associate Laboratory of Energy, Transports and Aerospace, Department of Mechanical Engineering, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal.
Materials (Basel, Switzerland)
|January 25, 2025
概括
这项研究评估了四种构成模型,用于预测环氧树脂的时间依赖性行为,这对于复合材料至关重要. 所有模型都显示出良好的预测性能,在卸载阶段注意到了一些差异.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物力学 聚合物力学
- 类风病学 类风病学 类风病学
背景情况:
- 环氧树脂在复合材料中至关重要,但表现出时间依赖的粘弹性行为,如爬行和应力放松.
- 这种依赖时间的响应在持续负载下可能导致故障.
- 现有的聚合物力学构成模型缺乏广泛的比较验证.
研究的目的:
- 评估和比较四个不同的环氧树脂时间依赖的组成模型的预测性能.
- 评估模型集成到实际的工程分析中.
- 为了确定在长时间的爬行负载下模型的推断能力.
主要方法:
- 商用环氧树脂在各种负载条件下进行实验测试 (恒定拉伸率,爬行,放松).
- 使用最小数据集对模型参数进行校准.
- 对模型预测与实验数据的评估,包括延长到五十年的爬行测试.
- 两个粘性弹性 (Schapery,Rabotnov),一个粘性塑性 (Norton-Bailey) 和汉堡模型的比较.
主要成果:
- 所有四种模型都对环氧树脂的依赖时间的机械反应表现出了令人满意的预测性能.
- 模型复杂性 (参数数量) 与预测准确度的提高没有直接相关.
- 在测试的卸载阶段,预测准确度出现了显著的差异.
结论:
- 评估的构成模型为预测工程应用中环氧树脂的时间依赖性行为提供了可行的工具.
- 该研究强调了模型验证在各种加载场景和时间尺度中的重要性.
- 进一步调查在卸载阶段的模型行为是有必要的,以进行全面的材料表征.
相关概念视频
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