1.Introduction

Generally, materials that can react to magnetic field are called magnetic materials, which can be divided into soft magnetic materials and hard magnetic materials according to the difficulty of magnetization. Soft magnetic materials are easy to magnetize and demagnetize. Soft magnetic materials are mainly used in automotive electronics, computers, home appliances, communications and other fields. They are also gradually widely used in new energy vehicles, automotive electronics, photovoltaic and other emerging fields. Soft magnetic materials are in the middle of the industrial chain and can be divided into metal soft magnetic materials and ferrite soft magnetic materials according to their resistivity. This paper mainly introduces metal soft magnetic materials.

2.Metal soft magnetic material

Metal soft magnetic materials are divided into:

1. Electrician pure iron (purity is generally above 99.8, used for iron core and magnetic pole of electromagnet)

2. Silicon steel: It has the characteristics of high magnetic permeability, low coercive force, and large resistivity, so the hysteresis loss and eddy current loss are small. It is mainly used as magnetic material in motors, transformers, electrical appliances and electrical instruments.

3. Metal magnetic particle core:

Metal soft magnetic powder core is made of metal soft magnetic powder,which is prepared by powder metallurgy after insulation coating treatment,, and has special functions of magnetoelectric conversion and energy storage filtering. Due to the existence of the insulating coating layer on the surface of the powder, the resistivity of the powder is effectively increased,it has lower loss under medium and high frequency conditions; At the same time, the thickness of the insulation layer is relatively thin, which has limited influence on the saturation magnetic susceptibility of the material.

It is mainly divided into iron powder core (the main component is iron, the magnetic permeability is between 10 and 75, suitable for low frequency occasions), sendust (magnetic permeability is between 14 and 125, no noise, low loss and suitable for high frequency occasions) , Iron-silicon (large saturation magnetic induction, small size, low loss), high flux (permeability between 14 and 125, low iron loss but high cost), MPP (iron-nickel-molybdenum, permeability at 14 ~125, iron loss is the lowest and most expensive in magnetic powder cores, suitable for military, aviation, and medical fields).

Relevant soft magnetic materials include FeSiAl, FeCoNi, FeSiCr, etc

Some metal powders and the physical picture are shown below (Changsha TIJO Metal Materials Co., Ltd.)

1.

Brand: FeSiAl soft magnetic powder

Features: excellent DC bias characteristics, higher saturation magnetic induction strength

Purposes: ferrosilicon magnetic core, choke coil, new energy vehicle and charging pile, etc

2.

Brand: FeCoNi soft magnetic powder

Features: better corrosion resistance, good temperature stability, lower loss

Purposes: magnetic shielding materials, wave-absorbing materials, new energy vehicles and charging piles, etc