A Study on the Soft Magnetic Properties and Compaction Density of Fe-based Nanocrystalline Powder Cores Mixed with Permalloy Powders

摘要

In this paper, the soft magnetic properties and compaction density of Fe-Si-B-Nb-Cu nanocrystalline powder cores, mixed with two kinds of permalloy powders (Ni70Fe30 or Ni50Fe50), have been closely studied. Permalloy powders having an average diameter of 4 m were added in the range of 5 to 15 wt%, and the powder composite was mixed with 1 similar to 2 wt% of water glass diluted with DI water. The powder cores were compacted in toroidal form at a pressure of about 35 tons, and then heat treated at 510 similar to 570 degrees C for 1 h. The magnetic properties of the soft magnetic composites (SMCs) were measured with a B-H analyzer and the microstructure was observed with FE-SEM. As a result, it was determined that the compaction density of the powder core increased with the increasing content of the mixed permalloy powder, which distinctly improved the composite's magnetic properties, including initial permeability and core loss.