摘要 |
A powder for a powder magnetic core, being composed of iron-base soft magnetic powder particles which each have a phosphoric acid-based chemical conversion coating on the surface. In this powder, the maximum thickness of the phosphoric acid-based chemical conversion coating is 20 to 200 nm, and recessed portions are formed on the surface of the chemical conversion coating with the total area of openings of the recessed portions being 0.5 to 50% by area relative to the total area of the observation visual fields, as determined by observing ten or more parts of the surface of the phosphoric acid-based chemical conversion coating through a scanning electron microscope with a magnification of 10000× or more. |