Development and types of soft magnetic materials
1.Development of soft magnetic materials
The application of soft magnetic materials in industry began at the end of the nineteenth Century. With the rise of electric power and telecommunication technology, low carbon steel has been used to make motors and transformers. In the core of the inductance coil of telephone lines, fine iron powder, iron oxide and fine wire are used. By the beginning of twentieth Century, the silicon steel sheet was developed instead of low carbon steel, which improved the efficiency of the transformer and reduced the loss. Until now, the steel in the electric power industry with a soft magnetic materials are still in the first place. By the 20s, the rise of radio technology promoted the development of high magnetic materials, and the magnetic powder core of permalloy and permalloy appeared. From 40s to 60s, the rapid development of science and technology, and the invention of radar, TV broadcasting and integrated circuits, and the requirement for soft magnetic materials were also higher. The soft magnetic alloy ribbons and soft ferrite materials were produced. In 70s, with the development of telecommunications, automatic control, computers and other industries, soft magnetic alloys were developed. Besides the traditional crystalline soft magnetic alloys, another kind of material, amorphous soft magnetic alloys, has sprung up.
2.Kinds of common soft magnetic cores
Three ferromagnetic elements, iron, cobalt and nickel, are the basic components of the magnetic material.
According to the (main components, magnetic characteristics, structural characteristics) classification of products:
（1）Pulverized core：MPP Cores，Include：Iron core, Iron silicon aluminum powder core, High Flux, MPP, Ferrite core.
（2）Iron core：Silicon steel sheets, Permalloy, Amorphous and Nanocrystalline Alloys.