Microstructure and Magnetic Properties of NANOPERM-Type Soft Magnetic Material

Abstract

In recent years, amorphous and nanocrystalline Fe-based alloys, due to their unique soft magnetic properties, have emerged as one of the most promising group of modern materials for various electric applications. This work presents microstructure and AC/DC magnetic properties of the NANOPERM-type material. The as-quenched amorphous Fe76Mo8Cu1B15 alloy was prepared by rapid quenching method in a form of 10 mm wide and 0.025 mm thick ribbon. Partial nanocrystallization was obtained by subsequent annealing of amorphous precursor at 783 K for 30 min. Microstructure investigation of annealed sample confirmed precipitation of α-Fe nanograins dispersed in amorphous matrix. In order to assess soft magnetic properties of fabricated material the dependences of core losses versus frequency (50 Hz-20 kHz) at room temperature were established, together with eddy currents, hysteresis, and anomalous losses coefficients separation. The frequency dependent correlation between real and imaginary part of permeability was also presented. Moreover, DC hysteresis loops of both as-quenched and annealed alloy were recorded in temperature range from 200 K to 400 K.

Two Fe-Zr-B-Cu Nanocrystalline Magnetic Alloys Produced by Mechanical Alloying Technique

“…In recent decades, several families of nanocrystalline soft magnetic alloys have been developed as alternatives to traditional ferrites such as Finemet [19], Nanoperm [20], Hitperm [21], or Nanomet [22]. Figure 1 shows the typical values of these nanocrystalline alloys, representing the initial permeability as a function of the saturation of the magnetic flux density.…”

Structural, Thermal and Magnetic Analysis of Fe75Co10Nb6B9 and Fe65Co20Nb6B9 Nanostructured Alloys

“…Soft and semi-hard magnetic materials are characterized by low-medium coercivity and high saturation magnetization. Among the multiple systems that have been analyzed, we should remark the Finemet, Nanoperm and Hitperm alloys, with elemental compositions Fe-M-Si-B-Cu, Fe-M-B-Cu and Fe-Co-M-B-Cu, respectively (M is an early transition metal) [ 2 , 3 , 4 ]. Thus, Hitperm alloys are characterized by the addition of Co and Fe as ferromagnetic metals, an early transition metal, such as Nb, Zr or Hf, a metalloid, such as B, P or Si, and a late transition metal, which is usually Cu.…”