Development of Fe-based amorphous alloys with high Bs and amorphous-forming ability

Summary form only given. Soft-magnetic amorphous alloys based on the ferromagnetic elements Fe, Co, Ni and their combination have attracted increasing interests since the discovery of the Fe-P-C system in 1967, because of their excellent soft-magnetic performances including high saturation flux density (B_s), low coercivity (H_c), high permeability, low core loss, and so on. By devoting subsequent great efforts, a variety of ferromagnetic amorphous alloys have been developed and many have been widely used such as various Fe-based, Co-based and FeNi-based amorphous alloys under the trademarks of METGLAS and VITROVAC with different performance. Nevertheless, owing to the restriction of amorphous forming ability (GFA), it is hard to further increase the B_s by increasing the Fe content. Development of ferromagnetic amorphous alloys with high B_s and amorphous-forming ability are tremendous desired. In this study, by introducing new amorphous-forming elements and adjusting composition, high Fe content Fe₈₃(Si,B,P,C)₁₇ amorphous alloys with excellent magnetic properties and high amorphous-forming ability were successfully developed . Together with the high B_s of 1 .67T, the alloys exhibit high amorphous-forming ability of more than 80 um which are greatly needed for wide amorphous alloy ribbon production by using common single-roller melt-spinning method . The ribbon samples annealed under the optimal conditions displayed good ductility and good soft-magnetic performance including low H_c of 2 .4 A/m and high μ_e of about 10000 . The mechanisms of good magnetic properties, high amorphous-forming ability and good ductility for these amorphous alloys were also discussed by analyzing the crystallization behaviors. The integration of excellent soft-magnetic properties and good manufacturability makes the FeSiBPC alloys promising soft-magnetic materials for industrial applica- ions .