Glass formation and magnetic properties of Fe-Hf-Zr-M (MÂ =Â metalloids Si, P, and B and metal Al) high-iron alloys

High iron content Fe-based amorphous alloys with high iron content and the nominal composition of Fe89Hf7Zr1M3 (M = metalloids Si, P and B and metal Al) were fabricated by melt spinning. When the added M varied among metalloids Si, P, and B and metal Al, the structure of the as-spun ribbons evidently transforms from crystalline and crystalline + amorphous to amorphous state. The amorphous structure only forms in the Fe89Hf7Zr1B3 and Fe89Hf7Zr1Al3 alloys. These alloys also exhibit a large difference in soft magnetic properties, such as magnetic induction Bs and coercivity Hc. In the amorphous state, the Fe89Hf7Zr1Al3 alloy exhibits higher Bs of approximately 1.60 T and lower Hc of about 4.3 A/m, which are markedly superior to those of the Fe89Hf7Zr1B3 alloy with Bs and Hc of approximately 0.64 T and 17.4 A/m, respectively. Compared with the metalloids Si, P, and B, the metal Al substantially decreases the onset crystallization temperature (Tx) and crystallization peak temperature (Tp), and the large temperature interval between the first onset crystallization temperature and the Curie temperature Tx1−Tc (exceeding 120 K) broadens the annealing temperature range. When annealed at 848 K for 0.5 h, the Bs of Fe89Hf7Zr1B3 alloy increases from 0.64 T to 1.44 T, and that of the Fe89Hf7Zr1Al3 alloy increases from 1.60 T to 1.72 T. The Fe89Hf7Zr1Al3 alloy possesses higher Bs and lower Hc than those of Fe89Hf7Zr1B3 alloy, thereby showing superior magnetic properties.