Soft magnetic properties and corrosion resistance of Fe-Co-B-M (M Nb, Ta and NbNi) metallic glasses

Fe-based metallic glasses (MGs) with good soft magnetic properties, high thermal stability combined with high corrosion resistance should have greatest potential for wide variety of applications. In this work, the effects of Nb, Ta and NbNi additions on the glass forming ability (GFA), thermal stability, magnetic properties and corrosion resistance of the as-spun Fe-Co-B-based amorphous ribbons have been investigated. The (Fe0.7Co0.3)75B21Nb4 and (Fe0.7Co0.3)75B21Ta4 MG possess the larger supercooled liquid region >40 K, presenting a high GFA. Via appropriate adjustment of the Fe/Co content ratio (4:1), the glass transition temperature and onset crystallization temperature of the (Fe0.8Co0.2)75B21Nb4 MG reach up to 800 and 826 K, respectively, indicating the best thermal stability. All the amorphous ribbons show the soft magnetic properties identified by the coercivity