In fact, it is really widely used: In fact, are widely used: permanent magnet motor, magnetic crane, magnetic chuck, magnetic actuator (synchronous transmission, hysteresis, eddy current drive), magnetic spring (The curve is opposite to the spring shape when they’re attracted), security sensors, sensor, de-ironing separator, separator, daily necessities, toys, tools, etc.
There are friends interested in the processing and molding of magnets, the following is a brief introduction:
The production process of NdFeb, colloquially speaking, is like this: the materials are mixed and melted, and then the refined metal pieces are broken into small particles. The small particles are pressed into a mold. And then sintered. Sintered out, is the blank.
The shape is usually square or cylindrical. Square blocks, for example, Dimensions are generally centered around 2 inches by 2 inches and about 1-1.5 inches thick. Thickness is the direction of magnetization (high performance magnets are oriented, so they have magnetization direction)
Then, according to the actual needs, the blank is cut into the required size and shape. Cut the magnet, chamfering, cleaning, electroplating, magnetization, and that is OK.
Orientation: NdFeb is an oriented magnet. In simple terms, the practical effect is that a square magnet has a strong magnetic field only in the orientation direction, and a much weaker magnetic field in the other two directions.
When you pull several magnets together, the oriented magnets can only be drawn in one direction, but can’t just stick it together.
This orientation is carried out when the blanks are pressed. This reason also limits the size of the blank size of the magnet, especially the height of the magnetization direction (generally the working direction, that is, the direction of the NS pole).
At present, the most reasonable height size of magnetization direction is generally no more than 35mm. High-performance, generally not larger than 30mm.
If you need a magnet of very large size in the magnetization direction what can we do? Several magnets can be stacked on top of each other, and the effect is similar to a series in an electric field.
Of course, this approach is not meaningful in practical use, the use of very few
Where can I buy NdFeb magnets? In fact, it is very easy to search the Internet to NdFeb manufacturers, small that kind, and then say you want to do what a product, the number is thousands or tens of thousands of a month, buy a few samples to test the performance.
If you say it well and the product is generic, you can get free samples. Or spend money. It’s not expensive. Don’t look for big manufacturer, somebody else basic ignore you.
Processing of NdFeb: there are basically two kinds: slicer cutting or line cutting.
Slicing machine, is a thickness of about 0.3mm diamond hole cutting blade, according to the requirements of the magnet cut into the required size. However, this method is only works with simple square and cylinder shapes. Because it is an inner hole cutting, the size of the magnet should not be too large, otherwise it cannot be placed inside the blade.
Another method is wire cutting. Generally used for cutting tiles, and large size products.
Drilling: small holes, usually drilled with vibrating diamond grinding wheel drill. Large hole, using the way of sleeve hole, so as to save the cost of materials.
The dimensional accuracy of NdFeb products, more economical, is about (+/-) 0.05mm. In fact, the existing processing means can achieve (+/-) 0.01 accuracy. However, because NdFeb is generally required for plating coating, cleaning before plating. The corrosion resistance of this material is very poor. In the process of pickling, the dimensional accuracy will be washed away.
Therefore, the real electroplating good products, the accuracy is less than the level of simple cutting and grinding.
Post time: Oct-18-2021