| In this article, FeZrB-base amorphous alloy ribbons were prepared by single roller melt-spinning method, crystal structures and soft magnetic properties of amorphous and nanocrystalline ribbons have been investigated by X-ray diffraction (XRD), differential scanning calorimeter (DSC), vibrating sample magnetometer (VSM) and precision magnetics analyzer. Effects of atom content ratio between Nb and Zr on crystal structure and soft magnetic properties have been studied in FeZrBCuNb alloys; Influences of the Ni content on the structure and properties have been researched by substituting a small amount of Ni for Fe in FeZrNbB ribbons. And feasibility of preparation of DM inductances with Fe-base nanocrystalline ribbons in inverter output filter circuit has been explored. The main results are as follows:1. For as-quenched Fe88Zr(7-x)B4Cu1Nbx(x=0,1,2,3,4) alloys, because glass formation ability of as-quenched ribbons were weaken with increase of the atom content ratio between Nb and Zr, the ratio should not been suggested more than3:4, but Increasing Nb content appropriately (x≤3at.%) would enhance initial temperature of primary crystallization process of a-Fe, and widen the range between initial temperatures of primary and secondary crystallization of the amorphous alloys, which is useful for improving the properties and thermal stability of nanocrystalline alloys. Amorphous ribbons annealed at550℃for30min would precipitate α-Fe phases. Nb would inhibit the the a-Fe grain growth during the annealing process, reducing the grain size and coercivity of ribbons. For amorphous Fe88Zr4B4Cu1Nb3ribbons annealed at580℃for30min, good soft magnetic properties were obtained:coercivity of6.2A/m, the permeability of21.4k, specific saturation magnetization of185.5emu/g.2. For as quenched Fe(86-x)Zr2Nb2B10Nix(x=0,1,3,5) alloys, the glass formation ability of as-quenched ribbons were improved with increase of the atom content ratio between Ni and Fe. Initial temperature of primary crystallization process of α-Fe would be elevated obviously with increase of Ni content, but the range between initial temperatures of primary and secondary crystallization of the amorphous ribbons appeared to narrow then widen. For amorphous Fe85Nb2Zr2BioNi1ribbons annealed below550℃for20min, single a-Fe phases were precipitated in alloys. The α-Fe grain size would grow up with increase of annealing temperatures, but not more than23nm. Annealed at520℃, the ribbons can achieve good soft magnetic properties with coercivity of8.3A/m, the effective permeability of48.4k(at1kHz), specific saturation magnetization of185.5emu/g, and core loss of less than10w/m3(Bm=180mT, f=300kHz). But when annealing temperature above the secondary crystallization initial temperature, such as600℃, Fe2B compounds would precipitate from the alloys. The a-Fe grain began coarsening with grain size up to50nm. The properties of ribbons appeared significantly worse.3. Fe-based nanocrystalline cores with closed magnetic circuit have the value of permeability up to one hundred thousand, but their stabilities of permeability on DC bias and frequencies were very poor. As a result, those cores could not be applied to output DM filtering circuit in the inverter directly. They are needed to gap within cores to improve the stabilities of permeability on DC bias and frequency, increase energy storage capacity of the inductance.4. The stabilities of inductance of Fe-based nanocrystalline core with a gap on DC bias and frequencies were greatly improved; the inductances could work normally in the DM filtering circuit, with output of sine wave voltage. In contrast to the inductances with Sendust magnetic powder cores in the circuit, the total harmonic distortion of sine voltage waveform would increase slightly.5. In contrast to inductance with Sendust magnetic powder core, the inductance with Fe-based nanocrystalline cores would reduce significantly in the scales and the amount of copper used for one inductance. Obtaining values of1.5mH, the former was1.3times of the later in the amount of copper used for one inductance,5times in the core volume and3.5times in core mass. |
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