磁流变弹性体微观预结构调控机理及宏观力磁耦合性质研究

Magnetorheological elastomer (MRE) is a kind of smart magneto-sensitive materials, which composes of magnetic particles and magnetically insensitive polymer matrix. The mechanical properties (e.g. stiffness, modulus, damping, etc.) of MRE can be altered by adjusting external magnetic field and thus makes MRE have much potential application in the fields of vibration control, magneto-dependent sensor design, etc. The macroscopic mechanical properties of MRE are strongly correlated with the microscopic particle-assembled structure of MRE. But the microstructure- based mechanism governing the macroscopic property of MRE has not been identified clearly. Given that, this research proposal attempts to study the particle aggregation of MRE in curing process, and then to reveal the microstructure-based mechanism of the macroscopic performance of MRE. Firstly, the analytical model of MRE will be constructed and the particle aggregation process will be studied by using particle dynamics simulation. As a result, the post-curing three-dimensional microstructure of MRE will be given. Successively, based on the post-curing microstructure, the magneto-mechanical coupling property of MRE will be computationally predicted by using finite element method and then comparatively studied by experimental test. Consequently, the relationship between the MRE’s macroscopic magneto-mechanical property and its microstructure will be further investigated. The implementation of this proposal will benefit the material preparation and the performance optimization of MRE, and go further to promote the MRE’s application in vibration control and magneto-dependent sensor design.

磁流变弹性体是一类力学性质（如刚度、模量、阻尼等）可通过外磁场进行调控的智能材料，其在结构振动控制、磁敏传感器设计等领域具有巨大的应用潜力。磁流变弹性体的宏观力学性质依赖于其微观磁敏颗粒聚集结构，但目前对支撑其宏观力学性质的微观结构机理的认识尚不明确。与现有研究相比，本项目不再直接对磁流变弹性体的微观颗粒聚集结构进行假定，而是拟应用颗粒动力学方法，重点研究磁流变弹性体在预结构过程中内部磁敏颗粒的运动机制及外磁场对颗粒聚集结构的调控机理。进而给出预结构成型后的三维微观磁敏颗粒聚集结构，并以该微观结构为基础，应用有限元方法对磁流变弹性体宏观的力磁耦合性质进行计算分析。然后对计算结果进行实验验证，以探究磁流变弹性体宏观力磁耦合性质与其微观磁敏颗粒聚集结构的关系。研究成果能够用于指导磁流变弹性体的材料制备和性能优化，可为进一步发展基于磁流变弹性体的振动控制技术和磁敏传感技术奠定基础。

本项目致力于掌握磁流变弹性体在预结构制备过程中内部磁敏颗粒的运动机制和外磁场对颗粒聚集结构的调控机制，揭示磁流变弹性体物理性质和其内部磁敏颗粒聚集结构之间的关系。项目研究了磁流变弹性体预结构制备过程中的磁性颗粒运动力学模型，考察了不同外磁场、不同磁性颗粒体积分数、不同基体粘度以及不同基体屈服强度对磁流变弹性体材料微观结构的影响。研究中应用颗粒动力学方法，成功地模拟了磁流变弹性体在预结构制备过程中微观磁性颗粒聚集结构的演化过程，给出了预结构成型后磁流变弹性体二维和三维微观结构模型。进而采用有限元分析方法，对磁流变弹性体的力学和传热学性质进行了计算分析。揭示了磁流变弹性体各向异性物理性质的微观结构基础。项目研究结果能够指导磁流变弹性体的材料制备和性能优化，并为进一步发展基于磁流变弹性体的振动控制和磁敏传感技术奠定基础。