| 摘要 |
PROBLEM TO BE SOLVED: To produce a sintered body having a fine and rigid high electric resistance layer on the surface of soft magnetic powder through a simple process using inexpensive soft magnetic powder principally comprising iron as a material. SOLUTION: Fe-Si alloy powder is heated in weak oxidizing atmosphere to form an SiO<SB>2</SB>oxide film on the surface and after being pressed, it is calcinated in weak oxidizing atmosphere to produce a sintered body. Surface oxidation process is carried out in weak oxidizing atmosphere of steam, or the like, to oxide Si selectively thus forming a thin oxide film of high electric resistance, which is then further calcinated in weak oxidizing atmosphere. The oxide film cracked at the time of press molding is repaired by repeating oxidation in pressurization atmosphere and degassing in pressure reduction atmosphere thus obtaining a high quality sintered body. COPYRIGHT: (C)2006,JPO&NCIPI
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