Fig. 1. Structural characterization. (a) XRD curves of ASQ and annealed samples. Inset shows thermal properties measured by DSC, in which the glass transition temperature (Tg) and crystallization temperature (Tx) are identified as 780 and 837 K, respectively. HRTEM images for (b) ASQ ribbons and samples annealed at different conditions of (c) 668 K at 400 K/min and (d) 748 K for at 400 K/min. The local ordering clusters were observed in annealed samples marked by the red dotted circle.

Fig. 2. The variation of coercivity (Hc) of ribbons annealed at various conditions. The samples were annealed at Ta = 668, 748, and 798 K for 10 min incubating, respectively.

Fig. 3. Structural evolution in reciprocal space. (a) Structure factor at different annealed conditions. The insets show the enlarged peaks of q1, q2 and q2', respectively. The inset of the top right shows the fitting process by pseudo-Voigt function. (b) The FWHM1 of q1 and FWHM2 of q2 versus coercivity [the diffraction intensity of the samples annealed at different conditions in the insets of Fig. 3(a) is shown by shifted along the vertical axis for visibility].

Fig. 4. Structural evolution in real space upon annealing at different conditions. (a) The pair distribution function, PDF(r). The top inset exhibits the enlarged view of the first maximum (r1). The bottom inset shows the fitting process for MRO by a power-law function. (b) The characteristics in short and medium ranges. The upper one shows the positions of r1 versus Hc, which were from the fitting results by the pseudo-Voigt function. The lower one exhibits the decay exponent versus Hc derived from the fitting process. (c) The differentiated PDF (ΔPDF) was calculated by ΔPDF(r)T = PDF(r)T - PDF(r)ASQ, to sensitively detect the temporal variations of the PDF during isothermal annealing. (d) Radial distribution functions, RDF(r). The top inset shows the fitting process for the first peak by pseudo-Voigt function, which is composed of two sub-peaks. (e) The coordination numbers, CNs, integrated from the first full peak, sub-peak I and sub-peak II, changing with Hc at various annealing conditions.

Fig. 5. Schematic diagrams describing atomic evolution of Fe76Si9B10P5 alloy during various isothermal annealing processes. Glasses I, II, III represents three amorphous states evolved from the annealing processes at different conditions. Glass I is evolved by self-adaptive expansion and shrinkage as poor activation energy. Glass III is instigated to be modulated in SRO and MRO coordinately by enough activation energy. Glass II is an intermediated state between Glass I and Glass III. The schematic diagram of the potential energy hypersurface is inset where the different kinds of glasses are indicated. Consequently, in Glass I, the various ferromagnetic regions are coupled heterogeneously, in which the magneto-anisotropy is still considerable. However, in Glass III, the coupled “homogeneous strong and weak ferromagnetic regions (HSWFRs)” gives decreasing of the magneto-anisotropy, leading to a magnetic softness.