Study on the static normal force of MRF in non-uniform magnetic field

• Published in: Journal of magnetism and magnetic materials Vol. 599; p. 172063
• Main Authors: Xiao, Yufan, Zheng, Jinan, Chen, Shumei
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.06.2024
• Subjects: MRF; Non-uniform magnetic field; Normal force; MRF; Non-uniform magnetic field; Normal force
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2024.172063

Nowadays, many scholars have been studied the normal force of MRF in the uniform magnetic field. However, the research on the normal force of MRF in the non-uniform magnetic field is relatively limited. The non-uniform magnetic field can cause the MRF to generate normal force of different sizes and directions to cope with different working conditions, thus the normal force generated in the non-uniform magnetic field require more attention. In this paper, a theoretical model of the normal force of MRF in the non-uniform magnetic field was developed based on the enhanced magnetic dipole model. The normal force of MRF within a unit area can be calculated based on this theoretical model. However, the magnetic induction intensity is different at different locations of the non-uniform magnetic field, which leads to the normal force generated by the MRF are not accurately calculated. Therefore, it is necessary to use COMSOL to establish the material model of the MCR-302 plate rheometer and MRF to verify the accuracy of the proposed model. Then a flat-plate rheometer was used to test the static normal force of the MRF in the non-uniform magnetic field. Finally, the simulation and experimental data were compared. The results show that the simulation result with the experimental data is a good agreement, which verifies the reliability of the theoretical model. The static normal force of the MRF increases with the increase of volume fraction and magnetic field intensity.