Nanocrystallization Behaviour of Amorphous Co67Fe4Cr7Si8B14 Alloy

The investigation addresses the structure of a Co-based alloy and its magnetic properties. The major applications of these materials are in the development of different sensors, which require materials with high permeability. The structure evolution processes need to be explored to clarify the main parameters determining the time-temperature stability. In the present paper, a nanocrystallization behavior of Co67Fe4Cr7Si8B14 amorphous alloy manufactured in the form of a ribbon was studied using X-ray diffraction and sample vibromagnetometry methods. The structure evolution induced by the 30min isothermal annealing at a temperature range of 450 - 700 °C was studied by the X-ray diffraction method, and crystallization with hcp-Co, fcc-Co, and Co2B nanophases was revealed depending on the annealing temperature. According to thermomagnetic measurements, the nanocrystallization process corresponds to a three-stage crystallization model. The crystallization onset temperature of the amorphous alloy was observed to be to equal540 °C. The Curie point and saturation magnetization of the as-quenched alloy were defined as 305 °C and 76 Am2/kg, respectively.