Formation and Soft Magnetic Properties of (Fe, Co)-RE-B Glassy Alloy with Large Thickness

Abstract

The glass-forming ability, thermal stability and magnetic properties have been investigated for a Fe₆₇Co_9.5Nd₃Dy_0.5B₂₅ glassy alloy with a large supercooled liquid region of 56 K prepared by the melt-spinning technique. The glassy phase is formed in the wide sheet thickness range from 19 to 203 \\micron. The glass transition temperature (T_g), crystallization temperature (T_x), supercooled liquid region (ΔT_x=T_x−T_g) and heat of crystallization (ΔH_c) remain almost unchanged in the thickness range below 203 \\micron. The Fe₆₂Co_9.5Nd₃Dy_0.5B₂₅ glassy alloy annealed at 773 K for 600 s exhibit good soft magnetic properties of 1.41 T for saturation magnetization (I_s), 2.6 A/m for coercive force (H_c), and 12000 for permeability (μ_e) at 1kHz in a thickness of 19 \\micron. The I_s, H_c and Curie temperature (T_c) remain unchanged in the thickness range up to about 200 \\micron, but the μ_e at 1 kHz gradually decreases to 6700 for the thick sheet with a thickness of 203 \\micron.