导向对聚甲酸的动态压缩特性的影响
Hongyu Lu1,2, Zitong Lu3, Xueting Xu1,2
1Beijing Institute of Aeronautical Materials, 100095 Beijing, China.
The journal of physical chemistry. B
|September 1, 2025
概括
双轴拉伸的聚甲酸 (BO-PMMA) 具有增强的动态压缩特性. 一个构成模型准确地预测它在各种应变速率和温度的行为,提供工程洞察力.
科学领域:
- 材料科学
- 聚合物物理
- 机械工程
背景情况:
- 聚甲酸 (PMMA) 对于透明结构至关重要.
- 双轴拉伸的PMMA (BO-PMMA) 与非定向的PMMA (UO-PMMA) 相比具有更好的机械性能.
- 了解方向对动态压缩的影响对于材料应用至关重要.
研究的目的:
- 研究双轴拉伸方向对PMMA动态压缩特性的影响.
- 为BO-PMMA建立一个适用于各种应变率和温度的构成模型.
- 阐明方向对PMMA压缩行为的影响背后的机制.
主要方法:
- 在BO-PMMA和UO-PMMA的动态压缩实验中,应变速率从1到4000s-1和温度为-40°C,RT和80°C.
- 应力-应变曲线的定量比较以分析方向效应.
- 杜安-赛加尔-格里夫-齐默曼 (DSGZ) 构成方程的适配参数.
- 使用已建立的DSGZ模型进行数值模拟和分析.
主要成果:
- 增加延展率或降低温度会增加PMMA的产量应力.
- 与UO-PMMA相比,BO-PMMA对应变速率和低温的敏感性更强.
- 开发的DSGZ模型准确地描述了BO-PMMA和UO-PMMA的动态压缩行为.
结论:
- 材料的方向对PMMA的动态机械反应有很大的影响.
- 已建立的构成模型为模拟和预测动态压缩下的PMMA行为提供了可靠的工具.
- 这些发现为面向PMMA的工程应用提供了宝贵的指导.
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