Particle interaction energy and hysteresis in polar and non-polar medium based magnetic fluids

Inner structural properties of two different types of magnetic fluids (MFs) under the application of an external magnetic field were investigated by using the ultrasonic propagation velocity method. Specifically, we thoroughly investigated a number of MF-inherent phenomena that are important for determining the ultrasound propagation velocity; these phenomena included the effect of the medium, particle interactions, anisotropy, Brownian motion, and hysteresis. Using the measured data, we show that it is possible to explain the observed structural changes in the polar- and non-polar-medium-based MFs. [Display omitted] •Ultrasonic propagation velocity was used to test inner structure of magnetic fluids.•Experimental data were analyzed by using Tarapov’s theoretical model.•Polar and non-polar medium based magnetic fluids were examined. The inner structural properties of two different types of magnetic fluids (MFs) under the application of an external magnetic field were experimentally investigated by using the ultrasonic propagation velocity method. Because the inner structure of the MF subjected to an external magnetic field mainly depends on parameters such as the medium, particle–particle interaction, and hysteresis, the ultrasonic velocity method was used to investigate the detailed structural formation of particles in both polar and non-polar medium based MFs. The experimental data were analyzed by incorporating the distribution of the particle moments by using Tarapov’s theoretical model. Based on the results, the inner structures of the prepared MFs were analyzed in terms of the effect of the medium, while the effects of Brownian mechanism and interaction phenomena in the presence of the external magnetic field were considered. In addition, the results presented reveal anisotropy and hysteresis in the MFs subjected to the external magnetic field.