Effect of minor Cu addition on phase evolution and magnetic properties of {[(Fe0.5Co0.5)0.75Si0.05B 0.20]0.96Nb0.04}100-x Cux alloys

Abstract

{[(Fe0.5Co0.5)0.75Si0.05B 0.20]0.96Nb0.04}100-xCux (x 0, 1, 1.5 and 2) alloys with different rapid solidification conditions were prepared by copper mold casting and melt spinning. The structures, the thermal and the magnetic properties were studied by X-ray diffraction, differential scanning calorimetry and vibrating sample magnetometry, respectively. Minor Cu addition obviously depresses the glass-forming ability of the alloys (critical glassy diameter dc < 1 mm) compared with [(Fe0.5Co 0.5)0.75Si0.05B0.20]96 Nb4 (dc 3 mm). The effect of Cu addition on the evolution of crystalline phases corresponding to different rapid solidification conditions was evaluated. The existence of (Fe,Co), (Fe,Co)3B, (Fe,Co) 2B and (Fe,Co)23B6 crystalline phases in {[(Fe0.5Co0.5)0.75Si0.05B 0.20]0.96 Nb0.04}100-x Cu x alloys influences the saturation magnetization compared with the corresponding glassy alloys. © 2009 IOP Publishing Ltd.