1. What is a samarium cobalt magnet? 

Introduced in the 1970s, samarium cobalt magnets were the first commercially available rare earth magnets. Their launch was revolutionary, triple the largest energy product of any other touch iron at the time. Before the introduction of samarium cobalt magnets, the standard magnetic material was alnico magnets. Samarium-cobalt magnets were the strongest magnets until their ever-increasing production costs prompted engineers to look for cheaper alternatives and formulate NdFeB magnets, which are now the strongest magnets in the world.


The most commonly used grades of samarium cobalt magnets are made from an alloy of approximately 35% (Sm) and 60% (Co) with small amounts of iron (Fe), copper (Cu), (Hf), (Z) and praseodymium (Pr). Certain grades of samarium cobalt magnets are made entirely of samarium and cobalt, which offer excellent corrosion resistance.


2. Temperature of Samarium Cobalt Magnet

Samarium cobalt magnets are called SmCo magnets, which belong to the rare earth permanent magnet series like NdFeB magnets. While they are not as powerful as neodymium magnets, they have two distinct advantages over neodymium magnets. They are in the higher temperature range and are more resistant to corrosion. And from 150 degrees Celsius, it will be better than NdFeB magnets with high temperature resistance. Usually, the maximum working temperature of ordinary NdFeB magnets is only 80 degrees Celsius. Therefore, in relatively high temperature environments or applications, samarium cobalt magnets are also a good choice.


Not only do samarium cobalt magnets excel at high temperatures, but they retain their magnetism even at temperatures below absolute dew (-273 degrees Celsius), making them popular for cryogenic applications.


3. Corrosion resistance of samarium cobalt magnets

Since most grades of samarium cobalt magnets contain little or no iron, which gives them excellent corrosion resistance, neodymium magnets typically contain 60-75% iron. Therefore, SmCo magnets generally do not require electroplating.


4. Magnetic properties of samarium cobalt magnets

Compared with NdFeB magnets, the magnetic properties are not as good as SmCo magnets, but they are stronger than ordinary ferrites, equivalent to low-grade NdFeB magnets.


5. Price of Samarium Cobalt Magnet

The disadvantage of samarium cobalt magnets is that they are expensive compared to neodymium magnets due to the cost of producing samarium. Like other rare earth magnets, they are also very brittle and therefore best suited for applications that do not require direct impact.


6. Application of Samarium Cobalt Magnet

Due to their properties, samarium cobalt magnets are most commonly used in applications requiring high temperature operation such as generators, pump couplings, sensors, electric motors, marine applications as well as automotive, aerospace, military, food and manufacturing.



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