分子动力学和实验分析的能量行为在压力放松期间在磁铁质弹性体的分子动力学
Nurul Hakimah Lazim1, Mohd Aidy Faizal Johari1, Saiful Amri Mazlan2,3
1Engineering Materials and Structures (eMast) iKohza, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia.
Scientific reports
|August 25, 2024
概括
分子动力学模拟揭示了压力放松如何影响磁铁质弹性体 (MREs). 这项研究量化了能量变化和分子动力学,为MRE设计和纳米技术中的故障预防提供了见解.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 聚合物物理 聚合物物理
背景情况:
- 磁铁质弹性体 (MRE) 有多种应用,但它们的性能受到应力放松的限制,这降低了材料性能和寿命.
- 在MRE应力放松过程中量化能量和分子动力学在原子层面上具有实验挑战性.
研究的目的:
- 通过分子动力学 (MD) 模拟,阐明在恒定应力下MRE的应力放松机制.
- 在MRE应力放松过程中对能量成分变化和分子动态进行定量分析.
主要方法:
- 使用和不同磁铁颗粒度 (50-80 wt%) 构建MRE模型.
- 进行MD模拟以模拟在恒定应变下压力放松的情况.
- 实验验证使用振荡式剪切流体计来确定线性粘弹性区域.
主要成果:
- 模拟MD证实压力放松发生在所有MRE模型中,储存能量减少8.63-52.7%.
- 使用80%重量的Fe粒子的MRE模型显示出最高的最终储能 (12,045kJ),归因于更强的分子内和分子间相互作用 (更高的潜力和范德瓦尔斯能量).
- 在80%重量Fe粒子MRE模型中,应力放松降低了动能 (9362kJ) 和平均平方位移 (20,318 Å2),表明分子动力学发生了变化.
结论:
- 模拟MD提供了一种强大的定量方法来理解MRE压力放松.
- 这些发现为防止材料故障和为纳米技术应用设计先进的MRE提供了关键的见解.
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