Anyone knows iron or other metal with iron included in magnetic materials, it comes up to me when I was a child, our teacher help us to do a experiment for iron bar attract small metal hardware after magnetized by a permanent magnet. The main difference between permanent magnet and soft magnetic materials is magnetic force remaining time. Normally, there are several main type for soft magnetic materials below,
Composition : Fe2O3, 71%, MnO, 20%, others : ZnO
High resistivity (10 ohm-cm)
Low magnetic core loss
Curie temperature: high
Shape: EE, EI, ER, PQ, RM, POT and other types.
Application: power transformers, EMI common mode filters, energy storage inductor, etc.
Composition: Fe2O3, 50%, NiO, 24%, others: ZnO
High resistivity (107 ohm-cm)
High operating frequency
Core magnetic loss is higher than Mn-Zn
Curie temperature: high
Type: DR, R, ring, etc.
Uses: Normal mode filters, energy storage inductor, etc.
Comparasion between different soft magnetic material: