The Crystallization Kinetics, Structural and Magnetic Properties of Fe72.5Ag2Nb3Si13.5B9 Amorphous Ribbons as Affected by Annealing
Mohammad Mahmuduzzaman Tawhid,
Sujit Kumer Shil,
Mohammad Tahmid Shihab,
Shibendra Shekher Sikder,
Mohammad Abdul Gafur
Issue:
Volume 6, Issue 3, September 2018
Pages:
60-66
Received:
3 August 2018
Accepted:
15 September 2018
Published:
22 October 2018
Abstract: The amorphous ribbon of composition Fe72.5Ag2Nb3Si13.5B9 has been prepared by rapid solidification technique under an atmosphere of pure argon and the amorphous nature has been confirmed by X-ray diffraction (XRD). The crystallization behavior and the nanocrystal formation have been studied by Differential Thermal Analysis (DTA) and XRD. The effect of annealing has been explained on the basis of XRD spectra. Magnetization measurements have been carried out using vibrating sample magnetometer (VSM). The activation energy for crystallization is evaluated by Kissinger’s plot. The peak temperature is found to be shifted towards the higher value with heating rate. The peak shift indicates the change of the values of Si-content of nanograins and therefore, the change of the lattice parameter of nanograins. At higher annealing temperature (Ta) the crystallization peak becomes smaller and displays diffused character meaning that substantial amount of crystallization of α-Fe (Si) phase has already been completed. The activation energy for α-Fe-(Si) phase is found to be 5.78 eV and 0.164 eV for before and after annealing respectively. The saturation magnetization (Ms) and Curie temperature (Tc) were found 114 emu/g and 305°C respectively. The sharp fall of magnetization at Tc is obtained which is an indication of homogeneity of the material.
Abstract: The amorphous ribbon of composition Fe72.5Ag2Nb3Si13.5B9 has been prepared by rapid solidification technique under an atmosphere of pure argon and the amorphous nature has been confirmed by X-ray diffraction (XRD). The crystallization behavior and the nanocrystal formation have been studied by Differential Thermal Analysis (DTA) and XRD. The effect...
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