空隙诱导磁性弹性 II 弹性对磁性弹性体的广泛调节
Rio Urano1, Mika Kawai1, Tetsu Mitsumata1
1Graduate School of Science and Technology, Niigata University, Niigata 950-2181, Japan. tetsu@eng.niigata-u.ac.jp.
Soft matter
|October 13, 2023
概括
当粒子度超过临界点时,磁性弹性体的刚度显著增加,形成链状结构. 这种反应即使在重复的磁场周期后也是一致的.
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
- 磁力学 磁力学 是一种
背景情况:
- 基于聚氨的磁性弹性体是具有可调节性质的先进材料.
- 这些弹性体的磁性反应受粒子大小和度的影响.
- 了解空隙形成和粒子行为对于优化弹性体性能至关重要.
研究的目的:
- 研究基于聚氨的磁性弹性体的磁场诱导的动态模量变化.
- 为了确定引发机械性质显著变化的磁粒子的临界体积分数.
- 探索粒子大小,空隙形成和磁反应之间的关系.
主要方法:
- 动态机械分析 (DMA) 用于测量磁场下的存储模量变化.
- 不同的磁粒子直径 (7微米和235微米) 和体积分数.
- 扫描电子显微镜 (SEM) 用于可视化微观结构和空隙形成.
- 循环磁场应用以评估稳定性.
主要成果:
- 创建空隙的临界体积分数被确定为7μm的0.47和235μm粒子的0.44.
- 在临界分数以上,由于粒子链形成,存储模量显著增加 (700μm颗粒高达74%).
- 佩恩效应和临界磁场表明,在临界体积分数处产生空隙.
- 对于不同颗粒大小,SEM揭示了不同的空隙形成机制.
- 弹性体在20个开关周期中表现出稳定的磁性反应.
结论:
- 在磁性弹性体中创建空隙使粒子运动和链形成成为可能,显著增强磁模量响应.
- 粒子大小决定了空隙形态和磁诱导模量变化的大小.
- 紧张,佩恩效应和磁场等关键参数可靠地检测空隙形成的开始.
- 这些发现对于设计各种应用的高性能磁性弹性体至关重要.
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