Magnetic properties of nanocrystalline Fe-Cu-Si-B alloys

Recently, nanocrystalline Fe-Cu-B and Fe-Cu-Si-B soft magnetic alloys with high saturation magnetic flux density more than 1.8 T and low coercivity of about 6 A m-1 were developed by annealing melt-quenched alloys containing 1.3 -1.5 at % Cu and 0 - 7 at % Si. In this work, the magnetic properties of annealed Fe77.5-xCuxSi15.5B7 alloys with high Si content prepared by melt spinning are reported. The appropriate Cu content in this alloy system shifted to Cu content higher than that of the reported Fe-Cu-Si-B alloys with high Bs. The annealed alloy with x = 2.0 showed the Hc of about 10 A m-1, the B8000 of 1.47 T, and low magnetostriction of +4.8 x 10-6.