Nanocrystallization studies in Co-rich amorphous alloys
Raul Valenzuela1995, Journal of Magnetism and Magnetic Materials
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Abstract
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Nanocrystallization from Vitrovac amorphous ribbons was studied using Mössbauer spectroscopy, transmission electron microscopy, and differential scanning calorimetry. Co-rich amorphous alloys demonstrated an increase in the residual amorphous phase's Fe content following crystallization. This resulted in enhanced hyperfine fields and Curie temperature, while crystallization of grains smaller than 15 nm led to significant softening of magnetic properties. Controlled thermal annealing at temperatures lower than crystallization temperature increased initial magnetic permeability by five times. The findings contribute to understanding magnetic behavior in these materials.
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PACS: 75.50.Bb 75.50.Kj 65.60+a 75.60 Ej 76.80.+y 61.05.C 61.05.Qr Keywords: Fe and its alloys Amorphous magnetic materials Thermal properties of amorphous solids and glasses Magnetization curves Hysteresis Mössbauer effect X-ray diffraction Mössbauer spectroscopy
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