Classification and introduction of advantages and disadvantages of magnetic core materials -

1. Ferrite Ferrimagnetic oxides mainly composed of Fe2O3 include Mn-Zn, Cu-Zn, Ni-Zn, etc., among which Mn-Zn is the most commonly used. Advantages: easy molding, low cost, high resistivity, and low high-frequency loss. Disadvantages: low saturation flux (4000~5000 Gauss), low Curie temperature point. Mostly suitable for 10K-500KHz frequency and lower power applications. Commonly used as high-frequency transformers, low-power energy storage inductors, etc. Ferrites with high magnetic permeability are also commonly used as EMI common mode inductors. Commonly used materials are PC40 from TDK, BH2 from TOKIN, N67 from Siemens, 3C90 from Philips, etc. 2. Silicon steel sheet An iron-silicon alloy formed by adding a small amount of silicon (generally below 4.5%) to pure iron. Advantages: easy to produce, low cost, and high saturation magnetic flux (about 12,000 Gauss). Disadvantages: low resistivity, high frequency eddy current loss. The general use frequency is not more than 400Hz, and it is most suitable for low frequency and high power. Commonly used as power transformers, low-frequency inductors, CTs, etc. Commonly used materials are oriented silicon steel Z11 (35Z155) of Nippon Steel Corporation. 3. Iron-nickel alloy (also known as permalloy or MPP) Permalloy often refers to iron-nickel alloys, and the nickel content is in the range of 30~90%. Advantages: high magnetic permeability, low loss, good high-frequency performance Disadvantages: high cost Due to the high cost, it is rarely used at present. 4. Iron powder core Iron powder core is a kind of soft magnetic material formed by mixing and pressing ferromagnetic powder and insulating medium, and there are scattered air gaps (the effect is similar to that of ferromagnetic materials). Commonly used iron powder cores are composed of carbon-based ferromagnetic powder and resin carbon-based ferromagnetic powder. Advantages: The magnetic permeability is relatively stable with the change of frequency, and the change with DC current is also relatively stable, and the cost is low. Disadvantages: low magnetic permeability, high loss at high frequency, and high temperature aging problems. Because of its good DC current superposition performance, it is often used for filtering and energy storage inductors with superimposed high-frequency components in power frequency or DC, such as PFC inductors, INV inductors, and energy storage inductors for BUCK circuits. Commonly used materials are -8, -26, -34, -35 series of MircoMetals. 5. Sendust core (also known as Sendust or Kool Mu) Composition: Composed of about 9%Al, 5%Si, 85%Fe powder. Advantages: lower loss, better cost performance. Disadvantage: The price is slightly higher than iron powder core. Its DC current superposition performance is better, and its loss is lower than that of iron powder core. It can replace iron powder core as the inductor of PFC in UPS and the output filter inductor of inverter. The commonly used material is Kool from Magnetics

Mu series, and Arnold's Sendust (Super-MSS) series.