Kang, Eun Young Chung, Young Hoon Ok, Myoung-Ryul Baik, Hong Koo 2024-01-21T01:06:01Z 2024-01-21T01:06:01Z 2021-09-05 2007-03-25 0921-5093 https://pubs.kist.re.kr/handle/201004/134522 Internal structure of magnetic core for high-frequency use could be divided into small insulating units to minimize eddy current loss. Accordingly, the powder size of Febal.Si9.6B14.4Nb4 (numbers indicate at.%) amorphous alloy should be small and covered with some degree of insulating layer for producing high-frequency magnetic core. In this investigation, formation of the insulating layer on the surface of Fe-based amorphous alloy powder was studied using wet oxidation method. The size of Fe-Si-B-Nb amorphous alloy powder used in this research was less than 75 mu m in diameter. Forming mechanism of surface cracks and consecutive oxide layers was explained and the thickness of insulating layer could be controlled by changing treatment time and concentration of HNO3 in the oxidizing solution. Even though the oxide layer on the powder surface was partially flaked off during hot-compacting process, sufficient electrical resistance was maintained to lessen eddy current loss effectively. (c) 2006 Published by Elsevier B.V. English ELSEVIER SCIENCE SA ALLOYS Research on the surface oxidation procedure of Fe-base metallic glass during wet oxidation treatment Article 10.1016/j.msea.2006.02.311 1 MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, v.449, pp.159 - 164 MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING 449 159 164 scie scopus 000245477800033 2-s2.0-33847237985 Nanoscience & Nanotechnology Materials Science, Multidisciplinary Metallurgy & Metallurgical Engineering Science & Technology - Other Topics Materials Science Metallurgy & Metallurgical Engineering Article; Proceedings Paper ALLOYS Fe-Si-B-Nb amorphous powder surface oxidation insulating coating magnetic core core loss