Effect of metalloid additives on the effectiveness of ultra-rapid annealing in Fe-B based nanocrystalline alloys.

• Effects of B, C, Si and P additions on Fe 86 B 14 prepared by ultra-rapid annealing (URA) were investigated. • The effectiveness of URA was affected by metalloid additives and the soft magnetic properties after URA were degraded. • Addition of 1 at% Cu was found to be effective in enhancing the effectiveness of URA. • Multiple compositions were identified to exhibit low coercivity (H c < 3 A/m) where high glass-formability is expected. The effects of metalloid additives (ML = B, C, Si and P) on the structural and magnetic properties were investigated for nanocrystalline Fe 86- x B 14 ML x alloys prepared by ultra-rapid annealing (URA) of melt-spun ribbons. It was found that the effectiveness of URA was affected by these elements and the soft magnetic properties after URA were degraded. Contrarily, addition of 1 at% Cu was found to be effective in enhancing the effectiveness of URA and coercivity (H c) after URA was reduced significantly by Cu addition. These effects of additives on the soft magnetic properties after URA were well understood by considering the activation energy of crystallization. [ABSTRACT FROM AUTHOR]