Microstructure to magnetic behaviour relationship of annealed Fe–TM–B–Cu alloys

Abstract The evolution of magnetic microstructure for Fe 80 Zr 4 Mn 3 B 12 Cu 1 and Fe 82 Zr 4 Nb 3 B 10 Cu 1 alloys is investigated as a function of different amount of the crystalline phase. With progressing crystallisation the intergranual phase is depleted in iron, and structurally as well as magnetically distinct regions occur. Together with ferromagnetic bcc-Fe nanograins they affect the resulting macroscopic magnetic properties. Good soft magnetic properties as well as low core losses and high-quality frequency characteristics are found after 0.5 h annealing at 773 K for Fe 80 Zr 4 Mn 3 B 12 Cu 1 and after 1 h annealing at 823 K for Fe 82 Zr 4 Nb 3 B 10 Cu 1 alloys.