Nonlinear Magnetic Properties of Magnetic Fluids for Automotive Applications


  • Barnabás Horváth
  • István Szalai



AC susceptometry, nonlinear susceptibility, ferrofluid


The external magnetic field required to activate a magnetic fluid in an industrial application is sufficiently large that magnetization is no longer a linear function of the external field strength, i.e. magnetic fluids exhibit nonlinear characteristics. The aim of our research was to develop a measuring system which is capable of determining the nonlinear AC susceptibility of magnetic fluids at discrete frequencies and in the presence of a high-intensity driving magnetic field. The measurement of susceptibility is based on the determination of the change in frequency of a low-intensity field, which is generated by an LC oscillator. The application of sinusoidal excitation to the material results in a variation in the susceptibility that modulates the frequency of the measured low-intensity field and in the appearance of higher-order harmonics of the driving field. The higher-order components of the nonlinear AC susceptibility are extracted from the measured response by Fourier analysis. By applying the measuring system, the nonlinear susceptibility of water-based ferrofluids (Ferrotec’s EMG 700) and its dependence on the magnetic field strength were investigated.

Author Biographies

Barnabás Horváth

Institute of Physics and Mechatronics, University of Pannonia, Egyetem utca 10, Veszprém H-8200, HUNGARY

István Szalai

Institute of Mechatronics Engineering and Research, University of Pannonia, Gasparich Márk utca 18/A, Zalaegerszeg H-8900, HUNGARY




How to Cite

Horváth, B., & Szalai, I. (2020). Nonlinear Magnetic Properties of Magnetic Fluids for Automotive Applications. Hungarian Journal of Industry and Chemistry, 48(1), 61–65.

Most read articles by the same author(s)