Influence of the Cooling Rate on the Curie Temperature Value for Amorphous Fe-Based Alloys

M. Nabiałek, K. Jeż Department of Physics, Częstochowa University of Technology, Armii Krajowej 19 Av. 42-200 Częstochowa, Poland

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The Curie temperature is one of the most important parameters for ferromagnetic materials. With increasing temperature, thermal vibrations in the crystal structure and changes in the settings of magnetic dipoles occur. The material goes from ferro- to paramagnetic state. This phenomenon is well described for materials with a crystal structure. In the case of amorphous alloys, the Curie temperature is not a discrete value but a temperature range over which a magnetic transition occurs. The paper presents the results of the research on the magnetic polarization of saturation as a function of temperature for rapid-quenched alloys. Samples of different diameters, i.e., 0.5, 0.75, 1 mm, were prepared. The thermomagnetic curves were measured using a Faraday magnetic balance in the temperature range from room temperature to 1100 K in a homogeneous magnetic field with a constant intensity of 0.7 T. Based on the analysis of the relationship (μ0MS)1/β, it was found that with the decrease in the cooling rate of the alloy, the solidification time of the alloy increased, and the atoms rearranged into further distances as Curie temperature value increased. For the return curves, the Curie temperature corresponding to the Fe2B crystalline phase was recorded. In this case, some changes were also noted depending on the cooling rate.

DOI:10.12693/APhysPolA.142.84 topics: Curie temperature, rapid quenched alloys, injection-casting method