| 摘要 |
Provided is a dust core excellent in flux density, iron loss, and mechanical strength. A production process of a dust core according to the invention includes a step of compacting a mixture obtained by mixing an iron-based soft magnetic powder for powder compact having a phosphate conversion coating film on the surface of an iron-based soft magnetic powder with a lubricant to obtain a powder compact, a heat treatment step of heating the resulting powder compact at 550°C or more but not more than 650°C in an inert atmosphere, and a heat treatment step of heating the heat-treated powder compact at 420°C or more but not more than 530°C in an oxidizing atmosphere. |
