Many friends don't know how to choose when using strong magnets. Let's share the difference between samarium cobalt magnets and neodymium iron boron magnets.
1. The composition of samarium cobalt magnet and NdFeB magnet is different
Samarium cobalt magnet is a magnetic material made of samarium, cobalt and other metal rare earth materials by proportioning, smelting into alloy, crushing, pressing and sintering. Rare earth metal samarium, rare earth metal cobalt, metal element iron, metal element copper, and a small amount of zirconium added; NdFeB magnets are tetragonal crystals formed by neodymium, iron and boron. Rare earth metal neodymium, metallic element iron, non-metallic element boron, a small amount of dysprosium, niobium and aluminum are added.
2. The properties of samarium cobalt magnets and NdFeB magnets are different
Samarium cobalt magnets have high magnetic energy product, low temperature coefficient, high working temperature up to 350 °C, and no negative temperature limit. When the working temperature is above 180 °C, its larger magnetic energy product, temperature stability and chemical stability are higher than neodymium. Iron boron permanent magnet material. The sintered NdFeB permanent magnet material has strong magnetic properties. Relatively speaking, the overall performance of samarium cobalt magnets is weaker than that of neodymium iron boron magnets.
3. The prices of samarium cobalt magnets and NdFeB magnets are different
For samarium cobalt magnets and neodymium iron boron magnets of the same performance size, the price of neodymium iron boron magnets is lower than that of samarium cobalt magnets. The content of iron in NdFeB magnets is high, the content of rare earth elements is low, and the price of iron is cheap, so the price of NdFeB magnets is cheaper. The rare earth elements samarium and cobalt in samarium cobalt magnets account for about 70%, so the price is slightly higher.
4. Samarium cobalt magnets and NdFeB magnets have different high temperature resistance, oxidation resistance and corrosion resistance capabilities
The content of iron in NdFeB magnets is very high, so it is easy to be oxidized and corroded, so electroplating treatment is required. The content of iron in samarium cobalt magnets only accounts for a small part, and they are basically rare earth and metal elements that are not easily oxidized and corroded.
5. The difference between the appearance of samarium cobalt magnets and NdFeB magnets
There is basically no difference in the appearance of the blank material. When it is made into a finished product, the finished NdFeB magnet is generally electroplated and has a bright appearance. Depending on the coating, there are various colors; while the samarium cobalt magnet does not need surface plating, so the finished product appearance is the same as the blank.
6. The difference between samarium cobalt magnet and NdFeB crystal structure
Samarium cobalt magnets and NdFeB have very similar crystal structures. The crystal structure of samarium cobalt is hexagonal, while neodymium iron boron is tetragonal. Both types of structures impart highly directional magnetism to rare earth magnets. These crystal structures concentrate the magnetic field tightly in a north-south direction. When material properties are so concentrated in one direction, it is called anisotropy.
7. The difference between samarium cobalt magnet and NdFeB stability
The remanence temperature coefficient of NdFeB is relatively large. The higher the temperature rises, the lower the remanence. The remanence temperature coefficient of samarium cobalt is very low. At the same temperature, the demagnetization of samarium cobalt is much less than that of NdFeB. In addition, NdFeB must be electroplated, otherwise it will be easily oxidized and corroded and weathered away. Samarium cobalt generally does not need electroplating, but if the use environment is harsh, the service life after electroplating will be longer and more beautiful.
