Attractional behavior between a ferromagnetic liquid and a magnetic field depending on the temperature of the liquid

Abstract

Experimental analysis was performed to identify if there is a change in the magnetic attraction between a ferromagnetic liquid and a stable magnetic field, depending on the temperature of the liquid. The analyzed ferromagnetic fluid was synthesized as a colloidal suspension of ferromagnetic iron ferrite particles Fe3O4 (II, III) (98%) in engine oil (Castrol Magnatec 20W-50) as a carrier fluid. In this experiment, the ferrofluid was analyzed at 15 different temperatures, within an interval between -11ºC and 90ºC. The results of the present investigation show a direct effect between the attraction force of the fluid and the magnetic induction due to the temperature change of the liquid. A decreasing tendency of the attraction force was identified as the temperature of the liquid increased, which can be described within three patterns of behavior: the first one between -11ºC and 24ºC, the second one between 24ºC and 35ºC, and the third one between entre 35ºC and 90ºC. Based on the analyzed results, this article exposes the possibility of explaining this behavior as a consequence that the magnetic saturation is not only a constant of the material but also dependent on its temperature.