Effects of Composition and Magnetic Fragmentation Process on Magnetic Properties of FeCuNbSiB Nanocrystalline Alloy

Nanocrystalline alloys Fe₇₄Cu₁Nb₃Si₁₅B₇ and Fe₈₁Cu₆Nb₁Si₇B₅ were annealed at 570 ℃and 520 ℃, respectively, then they were bonded with acrylate adhesive to prepare multilayer magnetic sheet composites.The effect of different composition on the magnetic properties of nanocrystalline magnetic sheets was studied.The results show that the loss value P_cm of Fe₇₄Cu₁Nb₃Si₁₅B₇ in the range of 100-600 mT(f is 100 kHz)is significantly lower than that of Fe₈₁Cu₆Nb₁Si₇B₅.However, when the frequency is above 1.8 MHz, Fe₈₁Cu₆Nb₁Si₇B₅ imaginary part permeability μ''is lower, and Fe₈₁Cu₆Nb₁Si₇B₅ exhibits better characteristics at high frequency.Under the same current, the DC-bias performance of Fe₈₁Cu₆Nb₁Si₇B₅ is relatively higher.In addition, with the increasing times of magnetic fragmentation, both the real part permeability μ' and attenuation of the two alloys decrease with the frequency increasing.In the frequency range of 100 kHz-30 MHz, the corresponding frequency f of the maximum imaginary part permeability μ'' of the two alloys shifts to high frequency with the increase of magnetic fragmentation times.