The material with magnetic permeability of about 10 has excellent frequency characteristics and good impedance temperature characteristics, which is the best material for radar and transmitter filter inductance. The material with magnetic permeability 33 is most suitable for high current inverter inductors from tens to hundreds of A. If the volume and temperature rise are not high, it can be used as output inductor of switching power supply and APFC inductor with frequency below 50KHz. Magnetic permeability 75 is a cost-effective material for differential mode inductance and energy storage inductance of about 20K.

Fe-Si-Al alloy

The material with high cost performance is the substitute of iron powder core (excluding iron powder core with low permeability). The iron-silicon-aluminum core was invented by the Japanese in 1930s. It was invented in Sendai county, so it is also called Xiandu alloy. Subsequently, in the early 1980s, it was made into magnetic powder core, also known as Sendust magnetic powder core, which we denoted as CS. The magnetic properties of Fe-Si-Al magnetic powder core are similar to those of Qualcomm magnetic powder core, and the loss is lower than that of Qualcomm magnetic powder core, but the price is much cheaper. So it has been widely used in recent years. As long as it can replace MPP and Qualcomm magnetic powder core, try to use Fe-Si-Al magnetic powder core. The standard composition of Fe-Si-Al alloy is: Al 5.4%; si 9.6%； The rest is iron. The control range of alloy composition for producing Fe-Si-Al magnetic powder core is: Al 5.2-5.6%; si 9.2-9.8%； The rest is iron. The Fe-Si-Al iron powder core used at low frequency (below 1kHz) has the highest effective permeability, which is μе 147. At present, the iron-silicon-aluminum magnetic powder cores produced and supplied by CSC in large quantities have the following performance grades: μ е 26; μе60; μе75; μе90; μе 125, etc. , is also the most commonly used. The saturated magnetic induction strength Bs of Fe-Si-Al magnetic powder core is 800- 1000 mt, and the ampere turns used are about 300. The compaction density of the product is 5.2-6.0.