Cobalt magnets, officially known as "samarium cobalt magnets," have a magnetic strength second only to neodymium magnets. The advantage is that it is not easy to rust and has excellent high-temperature resistance. However, this type of magnet has poor mechanical strength and is very prone to cracking, so attention should be paid when using it.

Neodymium magnet, also known as neodymium iron boron magnet. Among existing materials, the magnetic force is the strongest and can exert strong magnetic force in smaller sizes. The disadvantage is that it is easy to rust. Together with cobalt magnets, they are called rare earth magnets. It is a general term for strong magnets and is a type of artificial permanent magnet

The advantages of neodymium magnets are high cost-effectiveness, high remanence, high coercivity, high energy product, and easy processing into various sizes, such as disk magnets, ring magnets, rectangular magnets, arc magnets, and other shapes of magnets.