Bonded vs sintered neodymium magnets

Regarding the difference between bonded neodymium magnets and sintered neodymium magnets, there are many online introductions, why continue to provide this article? The main reason is that most of the introductions on the Internet are not comprehensive. Next, I will give a comprehensive introduction to the difference between sintered NdFeB and bonded NdFeB, and see their appearance, production and processing technology, density, magnetic force, surface treatment, and magnetization. What are the specific differences in terms of methods and prices?

First of all, let’s compare the appearance, can you see it by looking at the pictures without reading the introduction?”

Main shape picture of bonded neodymium magnet;

Bonded neodymium magnets usually have a black epoxy surface, with black or gray predominate.

The main shape picture of rare earth neodymium magnet;

Sintered neodymium magnets are usually galvanized or nickel-plated, with a silver-white appearance, and can also be epoxy-plated.

Comparison of production and processing technology of sintered and bonded neodymium magnets

Bonded NdFeB magnets are made by adding NdFeB magnetic powder to a binder. Bonding is actually injection molding. There are four main processing methods, namely calendering, injection molding, extrusion molding, and compression molding. Commonly used It is injection molding and compression molding. Compression molding is to mix magnetic powder and adhesive according to the proportion, after granulation and adding a certain amount of coupling agent, compression molding in the mold, curing at 120°~150°, and finally the finished product is obtained. . Using solid epoxy resin or phenolic resin, the addition amount is 1%~5%, and the permanent magnets can be bonded according to larger size and simple shape. Generally, cathodic electrophoresis, spraying, evaporation and other methods are used for coating protection.

Sintered NdFeB is formed by vacuuming and heating at high temperature. Generally, only blanks can be produced after sintering, and then through mechanical processing (such as wire cutting, slicing, grinding, etc.), they can become magnets of various shapes.

Bonded sintered neodymium magnet density difference;

The density of bonded NdFeB is about 6 g/cm3. The density of sintered NdFeB is about 7.5 g/cm3.

Magnetic difference between bonded and sintered neodymium magnets

The bonded NdFeB material contains less neodymium, so the performance is not as high as that of sintered NdFeB [Generally, the magnetic rings with relatively thin walls are bonded with NdFeB]

Price comparison of sintered neodymium magnets and bonded neodymium magnets;

The price of bonded NdFeB will be much cheaper. The specific price is due to the recent material fluctuations. Welcome to contact the business for consultation. The production of bonded NdFeB requires opening a mold, while sintered NdFeB does not.

Main shape difference;

Sintered neodymium magnets have a wider range of shapes, such as annular, round, square, cube, arc, with hole type, special-shaped and so on.

Bonded neodymium magnets are mainly ring-shaped, and can also be made into a square, circular arc, etc.

Magnetization method difference;

Bonded neodymium magnets are mainly based on multi-pole magnetization, such as radial multi-pole, axial multi-pole, View the magnetization direction and schematic diagram of the bonded neodymium magnet; https://www.dgcourage.com/xinwen/hyxw/308.html

Sintered neodymium magnets are generally magnetized, such as axial, radial, thickness, etc.

Application difference;

Sintered neodymium magnets are mainly used in electronics, motors, electrical appliances, electroacoustics, optical instruments, medical equipment, smart home, packaging handbags, toys, industry, health care and many other fields.

Bonded neodymium magnets are mainly used in permanent magnet motors and sensors in the fields of IT and office automation, smart home appliances, and automobiles.

The above is the introduction about bonded vs sintered neodymium magnets. If you have any questions, please contact us to inform you of the problems you encounter.

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