在玻璃聚合物中裂尖进化的纳米级机制:混合粒子连续体模拟
Saeed Norouzi1, Xinxin Deng1, Rachel Furge2
1Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technical University of Darmstadt, Peter-Grünberg-Str. 8, D-64287 Darmstadt, Germany. s.norouzi@theo.chemie.tu-darmstadt.de.
Soft matter
|October 1, 2025
概括
这项研究使用混合粒子连续模型在不同的压力条件下揭示了不同的聚合物断裂行为. 它确定了驱动纳米尺度裂生长和塑造聚合物特性的特定压力状态.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 纳米机械学 纳米机械学
背景情况:
- 了解聚合物中的纳米级裂机制对于预测宏观性质至关重要.
- 裂纹尖端的高局部应力会导致复杂的非线性和时间依赖的骨折行为.
研究的目的:
- 开发和应用混合粒子连续体方法来模拟纳米级聚合物断裂.
- 在不同的负载条件下调查裂生长模式和潜在的压力状态.
主要方法:
- 利用混合粒子-连续模型,将粗粒度分子动力学与裂纹尖端和连续力学相结合.
- 在平面应力和平面应变负载条件下模拟了一个中心裂变的聚合物样本.
主要成果:
- 在平面应力条件下观察到裂尖和显著的塑料变形.
- 在平面应变条件下确定了裂纹和裂纹现象.
- 描述了特定的压力状态,这些压力状态控制了在粒子层面的裂纹启动,生长和形态.
结论:
- 混合粒子-连续体方法准确地捕捉了聚合物裂变行为和边界条件.
- 显著的纳米级裂机制和由此产生的宏观性质取决于应用的应力状态 (平面应力与平面应力).
- 这种方法提供了有关材料设计和性能预测的聚合物故障机制的见解.
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