Effects of Cu cluster evolution on soft magnetic properties of Fe83B10C6Cu1 metallic glass in two-step annealing

• Published in: Journal of alloys and compounds 2017-01, Vol.690, p.281-286
• Main Authors: Xia, G.T., Wang, Y.G., Dai, J., Dai, Y.D.
• Format: Article
• Language: English
• Subjects: Amorphous materials; Cu clusters; Mössbauer spectra; Soft magnetic properties; Two-step annealing
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2016.08.150

Not all Cu clusters in Fe-based nanocrystalline alloys can significantly influence the soft magnetic properties. In this study, a density increment of beneficial Cu clusters serving as heterogeneous nucleation sites was obtained by the two-step annealing of the Fe83B10C6Cu1 alloy. The formation and growth of Cu clusters during pre-annealing process were investigated by Mössbauer spectra. An increase of saturation flux density (BS) from 1.76 T to 1.81 T and a distinct decrease of coercivity (HC) from 8.8 A/m to 3.2 A/m were achieved by the two-step annealing. The density increment of beneficial Cu clusters is believed to be the main reason why the two-step annealed Fe83B10C6Cu1 alloy has an increased BS and a decreased HC. •The evolution of Cu clusters was studied by Mössbauer spectra and corresponding hyperfine field distributions.•The largest number and most uniform size of Cu clusters were obtained by pre-annealing at 588 K for 10 min.•The grain size of α-Fe was reduced from 17 nm to 11 nm after the optimal two-step annealing.•The optimal BS and HC of Fe83B10C6Cu1 alloy by two-step annealed were 1.81 T and 3.2 A/m, respectively.