Effect of annealing on specific magnetization of Fe-Cr-Nb-Cu-Si-B with the partial replacement of Fe by chromium

Abstract

The samples Fe 73.5-x Cr x Nb 3 Cu 1 Si 13.5 B 9 [x=7, 9, 10 and 12.5 are prepared in the amorphous state in the form of thin ribbons by rapid quenching technique at wheel speed of 25 m s −1 in an Ar atmosphere. The composition was sintered at the temperature 450-8000 C for half an hour. The saturation magnetization (Ms) and Curie temperature (Tc) of these alloys decrease linearly with the increase of Cr content for the entire composition range due to dilution of Fe magnetic moment and weakening of exchange interaction between of magnetic atoms. The critical composition for disappearance of ferromagnetism fall of curve Ms with the replacement Fe by Cr, where the nearest neighbor coupling is longer dominant and intermediate range occur, giving rise to a significant portion of antiferromagnetic interaction. The Curie temperature decreases due the weaker interaction among the Fe magnetic moment. The structural relaxation is associated with the magnetization up to the annealed temperature 600°C and the chemical disorderness arise with reference to enhancement of M of annealed samples. M versus H curves sharply rise which indicates the formation of crystallization and it seems to ferromagnetic and for x=12.5 which is paramagnetic in the amorphous condition with Tc=246 K. This increase of M for the four samples are due to the evolution of ferromagnetic α-Fe (Si) nanograin crystal.

Growth Effect of Crystallites in Fe82Si8B10 Amorphous Ribbon

“…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. Consequently, the size and density of the nanocrystals and intergrain distances determine the soft magnetic properties of metallic alloys (Iqbal et al, 2019;Calvin et al, 2003). The phase identification and gran size has been confirmed with the XRD experiment for both as as-cast and annealed samples to determine the crystallization onset temperature to evaluate the abridgment of annealing temperature.…”

Development of Co-Rich Microwires with Graded Magnetic Anisotropy

“…Such features of stress-annealed samples must be attributed to the amorphous structure of as-prepared and all stress-annealed samples. Indeed, the influence of annealing on saturation magnetization can be relevant upon devitrification of the amorphous precursor [ 71 ]. However, in amorphous materials, the saturation magnetization value is determined by the chemical composition [ 22 ].…”