环氧聚合物和玻璃增强复合物的循环热力学负荷中的粘性弹性记忆效应:在可变初始应力和周期持续时间下进行实验研究和建模
Maxim Mishnev1, Alexander Korolev1, Alexander Zadorin1
1Department of Building Construction and Structures, South Ural State University, Chelyabinsk 454080, Russia.
Polymers
|February 13, 2025
概括
本研究模拟了循环负荷下环氧聚合物和复合材料的残余应力. 最初的应力水平极大地影响了纯环氧的应力积累,低应力显著放大了残余应力.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 机械工程 机械工程
背景情况:
- 循环热力学负荷可以在聚合物和复合材料中诱导复杂的应力状态.
- 了解剩余应力积累对于预测材料耐用性和性能至关重要.
- 环氧聚合物和玻璃增强复合材料在不同的热和机械条件下表现出明显的粘弹性行为.
研究的目的:
- 在环氧聚合物和玻璃增强复合材料中建模和解释应力状态的形成,包括残余应力积累.
- 研究初始机械和热应力对粘弹性行为的影响.
- 开发和验证一个包含记忆效应的基于Python的材料模型.
主要方法:
- 在循环热力学负荷下对粘弹性行为的实验研究.
- 为改进的三元凯尔文-沃伊格特材料模型开发Python脚本.
- 在不同温度下确定粘弹性参数 (E1,E2,粘度).
- 在不同的机械和热应力比率下分析应力积累.
主要成果:
- 纯环氧聚合物可以表现出显著的残余应力积累,高达初始应力的2.7倍 (2.1 MPa),受到初始负载条件的严重影响.
- 环氧体中的高初始应力抑制了由于主导的放松过程而导致的残余应力积累.
- 与纯环氧相比,玻璃增强复合材料的残余应力积累明显较弱.
- 建模结果表明与实验数据具有良好的定性和定量一致.
结论:
- 初始应力条件对于预测环氧聚合物中长期材料行为至关重要.
- 在玻璃增强塑料中加固可减轻残余应力积累.
- 开发的Python模型和方法有效地预测循环热力学负载下的应力-应变状态.
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