Investigation on the Adhesion Mechanisms of Magnetic Composite Particles with the Centrifuge Method

在上一个资助期间，机械工程和力学研究所开发了一种测量磁性复合颗粒与平板材料之间粘附力的方法。测量了不同颗粒和材料组合的粘附力。在第三个项目阶段，测量被扩展到测量颗粒之间的粘附力。测量是通过观察磁场中的粒子链来进行的。因此，使用了一种新开发的离心机，可以在离心过程中直接观察颗粒链。附着力可以根据链断裂处的离心力来计算。另一方面，研究了离心力场中泥沙的稳定性。除法向附着力外，还测量了切向附着力。在已知接触半径的情况下，可以计算出附着力矩，目的是弄清单个附着力分量对泥沙稳定性的贡献。

A method for the measurement of adhesion forces between magnetic composite particles and flat materials was developed at the Institute of Mechanical Engineering and Mechanics during the last funding periods. The adhesion forces of different particle and material combinations were measured. In the third project phase the measurements are extended in order to measure the adhesion forces between particles. The measurements are carried out by observing particle chains within a magnetic field. Therefore a new developed centrifuge is used, that allows the direct observation of the particle chains during centrifugation. The adhesion forces can be calculated according to the centrifugal force at the location of the chain fracture. On the other hand the stability of a sediment within a centrifugal field is investigated. Besides the adhesion forces in normal direction the adhesion forces in tangential direction are measured. With the known contact radius the adhesion moment can be calculated.The aim is to clarify the contribution of the single adhesion component on the stability of a sediment.