Parisa Rezaei-Shahreza , Saeed Hasani , Amir Seifoddini , Paweł Pietrusiewicz , Katarzyna Bloch , Marcin Nabiałek
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引用次数: 0
Abstract
This study investigates the structural and magnetic evolution of Fe74B20Nb2Hf2Si2 amorphous alloy across the as-cast state and three distinct crystallization stages. Mössbauer spectroscopy of the as-cast state revealed ferromagnetic amorphous phases characterized by broad, asymmetric spectral lines and hyperfine magnetic field distribution peaks in the 5–30 T range, with an average hyperfine field (P(Bhf)avg) of 19.9 T, lower than Fe80B20 (28.2 T) and FINEMET (22.8 T). It indicated that the magnetic ordering stabilized can be reduced by Nb and Hf through increased atomic spacing and structural disorder. Annealing promotes the formation of nanocrystalline phases such as α-Fe, Fe2B, Fe23B6, and Fe2(Hf, Nb), with P(Bhf)avg increasing to 29.9 T in the third stage, reflecting enhanced magnetic ordering due to the growth of α-Fe. Simultaneously, saturation magnetization (Ms) increased from 1.14 to 1.71 T, while coercivity (Hc) increased from 1.5 to 40 A/m owing to phase boundaries and domain wall pinning. The exchange stiffness (Aex) and spin-wave stiffness (Dsp) also increase, indicating stronger ferromagnetic coupling. Alongside, the total magnetic loss (P) increases significantly during crystallization due to domain wall pinning and a decrease in electrical resistivity. The Curie temperature (Tc) elevates from 622 to 653 K, attributed to Fe depletion and B and Si enrichment, intensifying Fe–Fe exchange interactions. Overall, the alloy exhibits superior magnetic properties (such as high Ms, Aex, and permeability) during the crystallization process. Therefore, this alloy can be a promising candidate for high-frequency magnetic applications.
期刊介绍:
The Journal of Non-Crystalline Solids publishes review articles, research papers, and Letters to the Editor on amorphous and glassy materials, including inorganic, organic, polymeric, hybrid and metallic systems. Papers on partially glassy materials, such as glass-ceramics and glass-matrix composites, and papers involving the liquid state are also included in so far as the properties of the liquid are relevant for the formation of the solid.
In all cases the papers must demonstrate both novelty and importance to the field, by way of significant advances in understanding or application of non-crystalline solids; in the case of Letters, a compelling case must also be made for expedited handling.