Choi Young, Wereley Norman M
Department of Aerospace Engineering, University of Maryland, College Park, MD 20742, USA.
Micromachines (Basel). 2024 Jun 14;15(6):782. doi: 10.3390/mi15060782.
This study focuses on the development and compressive characteristics of magnetorheological elastomeric foam (MREF) as an adaptive cushioning material designed to protect payloads from a broader spectrum of impact loads. The MREF exhibits softness and flexibility under light compressive loads and low strains, yet it becomes rigid in response to higher impact loads and elevated strains. The synthesis of MREF involved suspending micron-sized carbonyl Fe particles in an uncured silicone elastomeric foam. A catalyzed addition crosslinking reaction, facilitated by platinum compounds, was employed to create the rapidly setting silicone foam at room temperature, simplifying the synthesis process. Isotropic MREF samples with varying Fe particle volume fractions (0%, 2.5%, 5%, 7.5%, and 10%) were prepared to assess the effect of particle concentrations. Quasi-static and dynamic compressive stress tests on the MREF samples placed between two multipole flexible strip magnets were conducted using an Instron servo-hydraulic test machine. The tests provided measurements of magnetic field-sensitive compressive properties, including compression stress, energy absorption capability, complex modulus, and equivalent viscous damping. Furthermore, the experimental investigation also explored the influence of magnet placement directions (0° and 90°) on the compressive properties of the MREFs.
本研究聚焦于磁流变弹性体泡沫（MREF）的开发及其压缩特性，MREF是一种自适应缓冲材料，旨在保护有效载荷免受更广泛的冲击载荷影响。在轻压缩载荷和低应变下，MREF表现出柔软性和柔韧性，但在更高的冲击载荷和更高应变下会变得刚性。MREF的合成过程包括将微米级羰基铁颗粒悬浮在未固化的硅橡胶弹性体泡沫中。采用铂化合物促进的催化加成交联反应，在室温下制备快速固化的硅橡胶泡沫，简化了合成过程。制备了具有不同铁颗粒体积分数（0%、2.5%、5%、7.5%和10%）的各向同性MREF样品，以评估颗粒浓度的影响。使用Instron伺服液压试验机对置于两个多极柔性条形磁体之间的MREF样品进行了准静态和动态压缩应力测试。这些测试提供了对磁场敏感的压缩特性测量，包括压缩应力、能量吸收能力、复模量和等效粘性阻尼。此外，实验研究还探讨了磁体放置方向（0°和90°）对MREF压缩特性的影响。
