Structures and properties of nanocrystalline alloy with tension-induced anisotropy control

Nanocrystalline alloy Fe74Cu1Nb3Si15B7 has been annealed under the tensile stress applied along with ribbon axis, and the magnetic properties and structures were investigated. Due to the tension-induced anisotropy, the alloy shows a constant permeability with the strength of magnetic field and frequency. Also, the alloys exhibit flatter hysteresis loop with large tensile stress, from which, the anisotropy field H-a shows a linear relationship with tensile stress. Under the tension annealing process, the internal residual stress has been released, which leads to the core loss decreasing 67% compared to the weak tensile stress in same condition. It is therefore proposed that tension annealing can promote the uniform structure and intense-induced anisotropy, which can be used to tailor the magnetic property of nanocrystalline alloy.