Fe- and Co-based metallic glasses and nanocrystalline alloys as good magnetic materials, which have important application in power transportation, computer storage and read-write magnetic apparatus, have great economic benefit and wide application prospect. In these years, they have become one of the important research subjects.Fe91-xZr5BxNb4 (FZBN) nanocrystalline alloy system with low B content (x≤20) has been extensively studied because of its excellent soft magnetic properties and very interesting magnetic exchange interaction in amorphous state. However, the mechanism for the influence of B content on the glass forming ability (GFA), thermal stability, magnetic properties and exchange interaction is not yet clear in high B content above 20 at.% for Fe-based amorphous alloys, and is still argumentative. It is helpful to understand magnetic exchange interaction of Fe atomic couples in the Fe-rich amorphous alloy and prepare bulk glasses by investigation of effect of substitution of B for Fe on the glass forming ability, crystallization and magnetic properties in wider B content range. So we prepared Fe91-xZr5BxNb4 (FZBN) alloys and investigated the effects of B content on crystallization, glass forming ability and magnetic properties. It is found that GFA reaches maximum near eutectic composition of x=27.5. FZBN amorphous alloys crystallized in primary crystallization mode at low B content range of x≤20, but in eutectic mode at high B range of 20 |