Effect of silicon additions on the magnetic properties for Fe-based alloys

The effect of the Si additions on the magnetic properties is reported for the novel Fe_87-xTi₇Zr₆Si_x (x = 0, 2, 4, 6, 8, 10) alloy system. The 2 mm wide ribbon samples for each composition were prepared by the melt spinning technique, and their phase information and magnetic behavior were obtained from X-ray diffraction and a vibrating sample magnetometer (VSM) respectively. The Fe₈₇Ti₇Zr₆ system, reference alloy without Si (x =0), is fully amorphous and has both paramagnetic and ferromagnetic properties; all other alloys with Si additions (x = 2, 4, 6, 8, 10) form crystalline phases, mainly α-Fe, which causes a magnetic phase transition from paramagnetic to ferromagnetic materials. The saturation magnetization (M_s) increases with increasing amount of Si addition, up to 1.16 T at x = 10. Temperature dependent dynamic magnetization is also observed in the Fe₇₉Ti₇Zr₆Si₈ (x = 8) system. Since Fe₇₉Ti₇Zr₆Si₈ alloy contains both a crystalline and amorphous phase, magnetization increases above the measured Curie temperature (T_c = 604 K) as a result of a higher crystallization temperature (T_x) of Fe-based amorphous alloy.