聚碳酸的热史依赖变形:实验和建模见解
Maoyuan Li1,2, Haitao Wang2, Guancheng Shen2,3
1School of Aerospace Engineering, Xiamen University, Xiamen 361005, China.
Polymers
|August 14, 2025
概括
这项研究揭示了聚合物形成历史如何影响机械性能. 一个新的模型准确地预测了聚碳酸变形,考虑了热历史,以改进材料模拟.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物工程 聚合物工程
- 计算力学 计算力学 计算力学
背景情况:
- 聚合物变形受加工条件和服务环境的影响.
- 当前的模拟通常忽略了制造工艺 (如注塑成型) 热史对机械响应的影响.
- 了解形成和使用行为之间的联系对于准确的材料建模至关重要.
研究的目的:
- 通过结合其热史来研究注射成型聚碳酸 (PC) 的大变形行为.
- 开发和验证一个新的构成模型,以考虑形成过程对PC机械反应的影响.
- 为了弥合聚合物加工模拟和机械性能预测之间的差距.
主要方法:
- 使用注塑成型制备PC标本,使用各种热条件 (温度,持续时间) 进行注塑成型.
- 通过单轴拉伸试验进行实验性表征,在一系列拉伸速率 (10^-3到10^-1 s^-1) 和温度 (293 K到353 K) 中进行.
- 开发一个新的构成框架,通过用户定义的材料子程序集成到 ABAQUS/Explicit 中.
主要成果:
- 实验数据显示了应变速率,测试温度和化对PC应力-应变行为的影响.
- 开发的构成模型准确地捕捉了PC的弹性,屈服性,应变软化和应变硬化特性.
- 预测的应力-应变曲线与实验结果有很好的一致性,验证了模型的有效性.
结论:
- 聚合物形成期间的热史显著影响大变形行为.
- 新的构成模型有效地整合了形成效应,提供了更准确的预测PC的机械反应.
- 这种方法通过将制造工艺与使用中的性能联系起来,提高了聚合物行为模拟的性能.
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