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

经典的磁性杂化材料含有软磁性或硬磁性颗粒。因此，它们要么表现出主动的磁流变效应，要么表现出磁硬颗粒磁化后的被动磁流变特性。在德国和俄罗斯项目组的这个研究协会内，我们将磁性硬颗粒和软颗粒组合在弹性基质中，以提供主动和被动磁流变性能的组合。在此背景下，该研究协会的中心目标是基于对材料性质的详细微观理解来合成用于传感器应用的定制磁性杂化材料。在这里描述的子项目中，我们将继续研究磁性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颗粒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关于各种实验技术的系统研究后，我们在第二阶段关于这些材料的工作将集中在它们行为的特定方面。特别是对颗粒形态对复合材料磁力学性能的影响进行了详细的研究。在第一阶段得到的结果强调了两个不同的物理过程，这两个过程导致了独特的磁流变效应：粒子的旋转/取向和弹性基质中粒子的结构。因此，为了区分基质中的这些过程，将考虑基于磁性硬质和软质两种类型的球形和不规则颗粒的杂化材料的样品。子项目的另一个目标将是研究复合材料在确定的预加载条件下的响应。到目前为止，这是磁性杂化材料中一个相当被忽视的方面。然而，当试件在预加载条件下集成到装置结构中时，这一主题对于技术应用特别重要。此外，我们还将对粘弹性响应的各向异性进行研究，并对具有磁性硬质和复合填料的混合磁性材料的磁形变效应进行评估。这些问题是对预压条件的补充，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，我们预计该项目将提供关于磁性杂化材料微观结构变化与宏观性能之间关系的详细信息。这些信息将为某些材料性质的预测提供基础，这可以通过材料成分的相应变化来实现。

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.