The Influence of Heat Treatment on Irreversible Structural Relaxation in Bulk Amorphous Fe₆₁Co₁₀Ti₃Y₆B₂₀Alloy

Abstract

Amorphous materials contain structural defects, which play a key role in the magnetization process within the condition known as the approach to ferromagnetic saturation. This paper presents the results of magnetization studies, carried out on bulk Fe61Co10Ti3Y6B20 alloy when under the inuence of a strong magnetic eld. The alloy samples were obtained in the form of a rod 1 mm in diameter, and tested in the as-quenched state and after an isothermal annealing process, at a temperature below the crystallization temperature. It was observed that the heat treatment, carried out below crystallization temperature Tx, leads to irreversible structural relaxations, specically reorganizing the atomic conguration within the volume of the alloy into an amorphous structure.

Effect of Small Addition of Cobalt on Magnetic Properties and Internal Stresses Sources in the Form of Free Volumes and Pseudo-Dislocation Dipoles in Fe78CoXSi11-XB11 (x = 0 Or 2) Alloys / Wpływ Nieznacznego Dodatku Kobaltu Na Właściwości Magnetyczne Oraz Źródła Naprężeń Wewnętrznych W Postaci Wolnych Objętości Oraz Pseudodyslokacyjnych Dipoli W Stopach Fe78CoXSi11-XB11 (x = 0 Or 2)

“…For FeSiB alloy sample in the range of magnetic field from 0.21 t to 0.74 t a linear relationship of magnetization was observed, consistent with the 3 law of ferromagnetic saturation approach, while for the second of studied alloys the linear relationship was related to the 4 law of ferromagnetic saturation approach [9,12,14,26]. It means that the introduction of Co into the alloy, replacing Si resulted in the change of diffusion processes in the phase of solidification.…”

“…The factors present in the equation 2, related to the expression ΔM def are described with the dependencies 3, 4 and 5 [13,14].…”

Effect of structural relaxations within the amorphous structure on the magnetic properties of amorphous tapes from FeCoB family

“…The temperatures for the heat treatment are usually specified by the analysis of results of heat flow in the function of temperature (calorimetric -DSC) and the time is determined experimentally [24]. There are several types of heat treatment: impulse, short-term, and long-term [25][26][27][28]. It is difficult to describe them accurately, as the important parameter of those processes of annealing, besides the time, is also the temperature, which can take different values, depending on the demanded process.…”

Structural Relaxation in the Amorphous Alloys: FeMeMoCrNbB (where Me = Ni or Co)

“…However, the configuration of these defects is not stable and, even during the solidification process, partial relaxation of these defects can occur; the associated mechanisms include: migration of defects, annihilation of defects, substitution with different defects, and conglomeration of point defects ("free volumes"). Three-dimensional conglomerations of point defects are unstable and are subject to a decomposition * corresponding author; e-mail: 23kasia1@wp.pl process, which creates linear defects -so-called "quasidislocational dipoles" [5,6].…”