퍼멀로이 분말이 혼합된 철계 나노결정립 분말코어의 성형밀도와 연자성 특성에 관한 연구

Abstract: 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 μm were added in the range of 5 to 15 wt%, and the powder composite was mixed with 1~2 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 ~ 570 ℃ 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. (Received December 30, 2016; Accepted May 12, 2017)