由异质性引起的环氧树脂拉伸应力降低和应力度:一种结合分子动力学模拟和有限元素方法的多尺度方法
Naoyuki Shoji1,2, Takefumi Yamashita1,3
1Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan.
The journal of physical chemistry. B
|October 16, 2023
概括
环氧树脂中的异质性显著影响机械性能. 模拟显示异质模型更好地预测实验压力-应变行为,并揭示剪切带形成,与同质模型不同.
科学领域:
- 材料科学 材料科学 材料科学
- 计算力学 计算力学 计算力学
- 聚合物物理 聚合物物理
背景情况:
- 环氧树脂是广泛使用的聚合物,其机械性能受其内部结构的影响.
- 了解异质性的影响对于准确的材料建模和性能预测至关重要.
- 以前的研究经常简化了环氧树脂结构,可能忽视了关键的微观结构影响.
研究的目的:
- 研究结构异质性对环氧树脂机械性能的影响.
- 将模拟结果与实验数据进行比较以进行验证.
- 阐明在纳米尺度上不同交叉连接结构的作用.
主要方法:
- 结合粗粒度分子动力学 (CG-MD) 和有限元素方法 (FEM) 的模拟.
- 构建了环氧树脂的微米级异质和同质FEM模型.
- 使用CG-MD确定了异质模型的纳米级元素参数,反映了各种交联结构.
主要成果:
- 不同质的FEM模型准确地预测了实验压力-应变曲线.
- 与实验数据相比,均质模型高估了拉伸应力值.
- 不同质的模型表现出应变度和剪切带状结构,在同质模型中不存在.
结论:
- 材料异质性显著影响环氧树脂的机械反应.
- CG-MD和FEM合为模拟异质聚合物系统提供了一个强大的方法.
- 纳米级结构变异的准确表示对于可靠的聚合物机械性质预测至关重要.
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