Bulk Glassy Co{sub}43Fe{sub}20Ta{sub}5.5B{sub}31.5 alloy with high glass-forming ability and good soft magnetic properties

摘要

A new Co-based bulk glassy alloy Co{sub}43Fe{sub}20Ta{sub}5.5B{sub}31.5 exhibiting a large supercooled liquid region before crystallization and good soft magnetic properties was synthesized by the copper mold casting method. The glass transition temperature (T{sub}g) is 910K and the supercooled liquid region (ΔT{sub}x) reaches 70 K. The high thermal stability of the supercooled liquid enabled us to produce bulk glassy alloys with diameters up to 2 mm. These bull glassy alloys exhibit good soft magnetic properties, i.e., saturation magnetization of 0.5T, very low coercivity of 0.9 A/m and very high permeability of 40000 at 1kHz. It is noticed that the diameter of 2 mm is the largest value for Co-based bulk glassy alloys reported up to now. The success of forming the large-scale size Co-based bulk glassy alloy with high thermal stability of supercooled liquid and good soft magnetic properties is encouraging for future uses of bulk amorphous soft magnetic materials.