METHOD FOR PRODUCING POWDER FOR MAGNETIC CORE

摘要

PROBLEM TO BE SOLVED: To provide a method for forming a thin and uniform silicon dioxide film covering the whole of the surface of each grain in magnetic powder having a low silicon content in a short period of time. SOLUTION: The method for producing powder for a magnetic core comprises: an atmosphere holding step where magnetic powder mainly made of iron (Fe) and containing 0.3 to 1.0 wt.% silicon (Si) is held in an oxidizing atmosphere in which the partial pressure ratio Log(PH2O/PH2) of water vapor partial pressure (PH2O) to hydrogen partial pressure (PH2) reaches -4 to -1; and a heating treatment step where the magnetic powder is subjected to heating treatment at 900 to 1,200°C in an oxidizing atmosphere. COPYRIGHT: (C)2011,JPO&INPIT