Development of Ternary Fe-B-C and Quaternary Fe-B-C-Si Amorphous Alloys with High Glass-Forming Ability and High Magnetization

The various properties of the ternary Fe-B-C and quaternary Fe-B-C-Si amorphous alloys have been investigated. It was discovered that some ternary Fe-B-C amorphous alloys with the Fe content close to that of the Cr23C6-type metastable Fe23(B, C)6 phase exhibit a glass transition prior to crystallization on heating. The alloys with the glass transition also have high mass magnetization of 176~178 A m2/kg at room temperature in an as-quenched state. In addition, the glass-forming ability (GFA) of the alloys is significantly enhanced by the addition of 4 at% Si and by adjusting the composition toward the slightly lower Fe and higher B side while maintaining high magnetization of approximately 170 A m2/kg at room temperature in an as-quenched state. It was also confirmed that the amorphous powders of Fe-Cr-B-C-Si alloys could be produced by a conventional water atomization method and exhibit the low core losses of 305~362 kW/m3 at 100 kHz and 100 mT. The quaternary Fe-B-C-Si amorphous alloys with high GFA, high magnetization and low core losses are suitable for a core material of various magnetic components.