Experimental study of magnetic field driven properties of magnetic hybrid materials with complex internal interactions

经典的磁杂化材料包含磁软或磁硬颗粒。因此，在磁性硬颗粒磁化后，它们表现出主动磁流变效应或被动磁流变特性。在这个由德国和俄罗斯项目组组成的研究协会中，我们将磁性硬颗粒和磁性软颗粒结合在弹性体基质中，以提供主动和被动磁流变特性的组合。在这种情况下，研究协会的中心目标是基于对材料特性的详细微观理解，为传感器应用合成定制的磁性混合材料。在这里描述的子项目中，我们将继续研究磁杂化材料的磁场驱动特性。工作计划的重点将是基于磁性硬和软颗粒的弹性磁性混合材料，以及它们的混合物。在第一个资助期完成各种实验技术的系统研究后，我们在第二阶段对这些材料的工作将集中在其行为的具体方面。特别是，将对颗粒形貌对复合材料磁力学性能的影响进行详细研究。在第一阶段获得的结果强调了两个不同的物理过程，这两个过程负责独特的磁流变效应：粒子的旋转/取向和弹性矩阵内粒子的结构。因此，为了区分基体内部的这些过程，将考虑基于球形和不规则磁硬和磁软两种类型颗粒的杂化材料样品。子项目的另一个目标是研究复合材料在确定的预加载条件下的响应。迄今为止，这是磁性杂化材料的一个相当被忽视的方面。然而，当样品在预加载条件下集成在设备结构中时，该主题对于技术应用特别重要。此外，我们将进行粘弹性响应的各向异性研究，并评估具有磁硬和复杂填料的混合磁性材料的磁变形效应。作为预压条件的补充，这些问题也与技术应用高度相关。与研究协会其他工作组的密切合作将使我们能够找到对实验结果的适当解释。总而言之，我们期望该项目将为磁性杂化材料的微观结构变化与宏观性能之间的关系提供详细的信息。这些信息将为预测某些材料特性提供基础，这些特性可以通过材料成分的各自变化来实现。

Classical magnetic hybrid materials contain either magnetically soft or magnetically hard particles. Thus, they show either an active magnetorheological effect or exhibit passive magnetorheological properties after magnetization of the magnetically hard particles. Within this research association of German and Russian project groups we combine magnetically hard and soft particles in an elastomeric matrix to provide a combination of active and passive magnetorheological properties. In this context, it is the central goal of the research association to synthesize tailored magnetic hybrid materials for sensor applications based on a detailed microscopic understanding of the material properties. Within the subproject described here, we will continue a study of the magnetic field driven properties of magnetic hybrid materials. In focus of the working program will be elastic magnetic hybrid materials based on magnetically hard and soft particles, as well as mixtures of them. After completion of the methodical studies regarding diverse experimental techniques in the first funding period, our work on these materials in the second phase will be focused on specific aspects of their behavior. In particular, a detailed study of the influence of the particles’ morphology on the magneto-mechanical properties of the composites will be carried out. Results obtained in the first phase emphasize two different physical processes, which are responsible for a distinctive magnetorheological effect: rotation/orientation of particles and structuring of particles inside an elastic matrix. Therefore, in order to distinguish between these processes inside the matrix, samples of hybrid materials based on particles of spherical and irregular morphology of both magnetically hard and soft types will be considered. Another goal of the subproject will be a study of the composite’s response under certainly defined preloading conditions. To date, this is a rather neglected aspect of magnetic hybrid materials. However, this topic is of particular importance for technical applications, when a specimen is integrated in a device structure under preloading condition. Moreover, we will perform a study regarding the anisotropy of the viscoelastic response and an evaluation of the magnetodeformational effect for hybrid magnetic materials with a magnetically hard and complex filler. Complementary to preloading conditions, these issues are as well highly relevant for technical applications. A close cooperation with other working groups of the research association will allow us to find appropriate interpretations of the experimental results. In total, we expect that the project will provide detailed information about the relation between microstructural changes and macroscopic properties of the magnetic hybrid materials. This information will provide the basis for a prediction of certain material properties, which can be achieved by respective changes in composition of the material.