Effect of Co content on microstructure and properties of FeCoZrB alloys

Fe76Zr9B15, Fe57Co19Zr9B15 and Fe38Co38Zr9B15 alloys prepared by melt-spinning were annealed at different temperatures. The crystallization behavior, microstructure and magnetic property of the alloys were investigated by differential thermal analysis (DTA), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). The results show that the crystallization activation energies of Fe76Zr9B15, Fe57Co19Zr9B15 and Fe38Co38Zr9B15 alloys are 363.50 kJ/mol, 434.86 kJ/mol and 536.33 kJ/mol, respectively. The initial crystallization product of Fe76Zr9B15 alloy are Fe23B6 type and α-Fe phases. The initial products of Fe57Co19Zr9B15 alloy are α-Mn type and α-Fe(Co) phases. The initial product of Fe38Co38Zr9B15 alloy is α-Fe(Co) phase. With increasing annealing temperature, Hc of (Fe1-xCox)Fe76Zr9B15 (x=0, 0.25, 0.5) alloys is different due to their different crystallization products. ©, 2014, Editorial Office of Transactions of Materials and Heat Treatment. All right reserved.