Effect of miscible and immiscible element microalloying on crystallization behavior and soft magnetic properties of Fe-P-C-B amorphous alloy

Microalloying is an efficient strategy to promote nano-crystallization of Fe-based amorphous alloys to improve soft magnetic properties. Here, the Fe-P-C-B amorphous alloy is selected as a typical system to investigate the effect of microalloying of immiscible elements (In and Sn) and miscible elements (Al, Ga and Ge) in Fe on crystallization behavior and soft magnetic properties of Fe-based amorphous alloys. Microalloying of immiscible elements leads to slightly increased energy barrier for alpha-Fe nuclei growth as evaluated by Kissinger equation, yielding fine and uniform alpha-Fe nanograins and low coercivity after annealing. In contrast, miscible elements cause high growth energy barrier, resulting in few huge alpha-Fe grains and large coercivity. This work suggests a strategy of obtaining amorphous-nanocrystalline alloys with good magnetic properties by microalloying of immiscible elements.

Automated summary

Microalloying is an effective strategy to enhance the nano-crystallization and improve the soft magnetic properties of Fe-based amorphous alloys. The effect of microalloying of immiscible elements (In and Sn) and miscible elements (Al, Ga, and Ge) in Fe on the crystallization behavior and soft magnetic properties of Fe-P-C-B amorphous alloy was investigated. Microalloying of immiscible elements leads to the formation of fine and uniform alpha-Fe nanograins with low coercivity, while the addition of miscible elements results in the growth of few large alpha-Fe grains and high coercivity. This study suggests a strategy of obtaining amorphous-nanocrystalline alloys with desirable magnetic properties by microalloying of immiscible elements.