High Bs nanocrystalline Fe84-x-yCuxNbySi4B12 alloys (x=0.0-1.4, y=0.0-2.5)

In this study, Cu and Nb content dependences of magnetic properties for annealed Fe84-x-yCuxNbySi4B12 alloy ribbons fabricated by melt spinning were investigated. In Fe83-xCuxNb1Si4B12 alloy systems, the coercivity H-c markedly decreases with increasing x and exhibits a minimum at around x =1.0-1.2, while the saturation magnetic flux density B-s shows a slight variation. In Fe83-yCu1NbySi4B12 alloy systems, H-c markedly decreases at around y = 0.5, while B-s shows a monotonic decrease. Fe82Cu1Nb1Si4B12 nanocrystalline alloy ribbons exhibit a high B-s of 1.78 T and a low Hc of 3.2 A/m. The core losses of the present alloys at 1.0 T at 400 Hz, P-10/400, and at 1.0 T at 1 kHz, P-10/1k, are 1.3 and 4.4 W/kg, respectively. (c) 2009 Elsevier B.V. All rights reserved.