Optimization of thermal stability and soft-magnetic properties of FeSiBPCuNb alloys by Nb content tuning

The effects of Nb content on the thermal stability, microstructural evolution and soft-magnetic properties of nanocrystalline Fe83-xSi4B10P2Cu1Nbx alloys were systematically investigated. Appropriate Nb addition was found to be effective both in prolonging operative annealing time and annealing temperature range and in improving magnetic softness by tuning the size and distribution of nano-sized alpha-Fe inclusions. The effective annealing time of 30 min over temperature range of 723-793 K, in combination with desirable soft-magnetic properties including high saturation magnetic flux density (B-s) of 1.73 T, low coercivity (H-c) of 4.5A/m and high effective permeability (mu(e)) of 23,000 at 1 kHz, entitles Nb-containing Fe82Si4B10P2Cu1Nb1 nanocrystalline alloy a truly industrial advantage in energy-economic efficiency and great potentials in electromagnetic applications. (C) 2014 Elsevier B.V. All rights reserved.