Thermal effect on structural and magnetic properties of Fe₇₈B₁₃Si₉annealed amorphous ribbons

Abstract

Abstract. In the present work, we study the influence of thermal treatments on the magnetic properties of as-quenched and pre-crystallized Fe 78 Si 9 B 13 after stress relaxation. The crystallization behavior of amorphous and treated Fe 78 Si 9 B 13 ribbons was revisited. The measurements were carried out by means of Differential Scanning Calorimetry, by X-ray diffraction and by Vibrating Sample Magnetometer, Susceptometer and fluxmeter. Relaxed samples were heated in the resistivity device up to 700°C and annealed near the onset temperature about 420°C for respectively 1, 3, 5, 8 hours. In asquenched samples, two transition points occur at about 505°C and 564°C but in relaxed sample, the transition points have been found about 552°C and 568°C. Kinetics of crystallization was deduced for all studied samples. Annealing of the as-purchased ribbon shows the occurrence of Į-Fe and tetragonal Fe 3 B resulting from the crystallization of the remaining amorphous phase. The effects on magnetic properties were pointed out by relating the structural evolution of the samples. The magnetic measurements show that annealing change the saturation magnetization and the coercive magnetic field values, hence destroying the good magnetic properties of the material. The heat treatment shows that the crystallization has greatly altered the shape of the cycles and moved the magnetic saturation point of the samples. The effect of treatment on the magneto-crystalline anisotropy is also demonstrated.

Growth Effect of Crystallites in Fe82Si8B10 Amorphous Ribbon

“…It is well known that low temperature annealing will reduce the Hc as a result of the internal stress relief reducing magnetoelastic anisotropy and re orientation of the easy magnetization direction (Dai et al, 2017). Important thermodynamic parameter primary crystallization corresponds to the precipitation of an ordered bcc α-Fe(Si) solid solution embedded in an amorphous phase and secondary Fe2B phase for effect on the crystallization process (Sikder et al, 1999;Soltani et al, 2017;Öztürk et al, 2019). The Crystallites gran size and the percentage of Si content with heating temperature of such novel materials exhibits interesting properties including physical, chemical, magnetic and electrical properties compare to conventional coarse-grained counterparts.…”