Iron-based nanocrystalline alloy is an amorphous material formed by a rapid solidification process of an alloy composed of iron as the main element and a small amount of Nb, Cu, Si, and B elements. After heat treatment, the amorphous material It can be obtained with a diameter of nanometer level and dispersedly distributed on the amorphous matrix, which is called microcrystalline and nanocrystalline materials.
Nanocrystalline materials have excellent comprehensive magnetic properties: high saturation magnetic induction (1.2T), high initial magnetic permeability (8×104), low Hc (0.32A/M), low high frequency loss under high magnetic induction (P0 .5T/20kHz=30W/kg), the resistivity is 80μΩ/cm, which is higher than permalloy (50-60μΩ/cm), and high Br (0.9) or low Br value (1000Gs) can be obtained by longitudinal or transverse magnetic field treatment ). It is a material with relatively good comprehensive performance on the market at present, and the normal frequency range is 20kHz-50kHz. Widely used in high-power switching power supply, inverter power supply, magnetic amplifier, high-frequency transformer, high-frequency converter, high-frequency choke core, current transformer core
, leakage protection switch, common mode inductor core.
The magnetic permeability and Hc value of nanocrystalline alloy are close to crystalline high permalloy and cobalt-based amorphous, and the saturation magnetic induction Bs is equivalent to that of medium nickel permalloy, and the heat treatment process is simple. It is an ideal low-cost high-performance soft magnetic Material
; Although the Bs value of nanocrystalline alloy is lower than that of iron-based amorphous and silicon steel, its high-frequency loss under high magnetic induction is much lower than them, and it has better corrosion resistance and magnetic stability. Compared with ferrite, nanocrystalline alloy has 2 to 3 times higher working magnetic induction on the basis of lower loss when it is lower than 50kHz, and the magnetic core volume can be more than doubled.