Effect of Fe on the structure and magnetic properties of Sm–Co–Cu–Fe–Zr melt-spun ribbons

The Sm12Co60−xCu6Fe19+xZr3 (x = 0–10) ribbons are prepared by melt-spun at 20 m/s, and the effects of Fe content on structure and magnetic properties of the ribbons are studied. It is observed that all as-spun ribbons are composed of Sm(Co,M)7 phase and small amount of α-Fe phase. Fe addition does not change phase composition of the ribbons. However, Fe can supersaturatedly dissolve in Sm(Co,M)7 and constrain the amount of α-Fe in the melt-spun ribbons. 1:7H phase in the x = 3 ribbons starts to decompose when the ribbons are annealed above 800 °C, that is, SmCo 1:7H → SmCo 1:5H + SmCo 2:17R + α-Fe. α-Fe is shown as precipitated phase, and all these precipitated phases are distributed in the form of fine needles. Magnetization of all melt-spun ribbons is determined by nucleation field; And magnetization of the x = 3 ribbons annealed at different temperatures is determined by different coercivity mechanisms. In the maximum applied field of 20 kOe, x = 1 ribbons annealed at 800 °C gets the highest coercivity of 2.262 kOe; x = 5 as-spun ribbons gets the highest remanence of 36.94 emu/g.