The invention discloses a preparation method of a high-frequency and high-stability carbonyl ferromagnetic
powder core, and belongs to the field of magnetic functional materials. On the basis of organic and inorganic
composite coating, a uniform and high-resistance SiO2 insulating
coating layer is formed on the surface of
carbonyl iron particles by adopting a simplified insulating
coating process, and the process does not need to adopt a
silane coupling agent to perform
surface modification on
carbonyl iron powder so as to control the thickness of the SiO2
coating layer within a reasonable interval; weakening of the magnetic performance of the
magnetic powder core caused by introduction of the non-
magnetic phase is reduced to the maximum extent; the formed
magnetic powder core does not need to be subjected to heat treatment, the onion layered special structure of the
carbonyl iron powder particles is prevented from being damaged, the preparation process is simplified,
operability is high, and the
raw material cost is low. According to the preparation method, the
bulk resistivity of the material is greatly improved, the
magnetic core loss under the high-frequency condition is reduced, the quality factor, the direct-current anti-saturation characteristic, the magnetic
conductivity temperature coefficient and the magnetic
conductivity frequency change rate of the carbonyl ferromagnetic powder core are optimized, and the prepared
magnetic powder core obtains high stability within the high-frequency range of 1-40 MHz.