With the increasingly serious environmental problems, electric vehicles (EVs) and hybrid electrical vehicles (HEVs) are in excess of a pattern and will additionally speed up throughout the next few years. There are also some challenges in this process.
SMC technology makes it possible to design cost-efficient, innovative, compact and high-performance electric motors.
Soft magnetic composites manufacturing process:
1) Selection of raw materials: high purity and high compressibility of water atomized iron powder, sponge iron powder or iron-based alloyed powder (containing Si, Ni, Al, Co and other elements) as raw materials;
2) Powder insulation coating and mixing process: Use organic or inorganic materials to coat iron powder, add binders, lubricants, etc. to make the powder fully mixed;
3) Forming and pressing: the mixed powder is poured into a rigid mold for pressing;
4) Heat treatment: the temperature is generally controlled between 400-700℃;
5) Surface coating or paint spraying: In order to achieve the purpose of anti-rust and insulation (This step is optional according to the actual situation).
High purity iron powder + organic materials -> mixing -> pressing -> heat treatment -> cleaning -> surface treatment -> finished SMC parts
The advantages of SMCs compared with traditional silicon steel sheets:
| SMCs | silicon steel sheets | Benefits of SMCs |
|---|---|---|
|
3D magnetic circuit |
2D magnetic circuit |
developers may regain the control over motor shape, size and output, so motors can be designed to suit the applications |
|
Isotropic thermal property |
Anisotropic thermal property |
increasing heat dissipation |
|
iron particles are insulated by the surface coating and adhesive |
None |
Low loss at medium and high frequencies |
|
Using powder metallurgy pressing technology, simple processing，production cost can be greatly reduced |
The processing technology is very complicated |
Suitable for large volume production, manufacturing of low cost electrical equipment |
|
It is possible to press parts with very complex structure at one time. |
It is not easy to process complex structural parts |
It can realize the design of claw machine motor and transverse flux motor |
|
SMC parts can be made with smooth corners in the teeth |
It is very difficult to make very smooth corners in the teeth |
This allows thinner slot insulation, resulting in better heat dissipation and more room for the winding |
|
The utilization rate of the materials is as high as 97% |
The utilization rate of the material is about 50% of powder metallurgy |
It is the cost effective and environmentally friendly |
