There are many types of permanent magnets in the commercial market today, such as neodymium iron boron magnets, samarium cobalt magnets, alnico magnets and ferrite magnets. Each type of permanent magnet has its own unique characteristics that affect its performance in various applications. For many people who are not familiar with permanent magnet materials, it is difficult to choose a suitable permanent magnet to meet their needs.
There are three important parameters for selecting permanent magnets:
1. Operating temperature
One of the most important parameters when selecting a permanent magnet is the temperature of use.
If you want to choose a permanent magnet with an operating temperature of 500°C, it is recommended that you choose an alnico magnet. It can withstand operating temperatures of 500°C and is the highest temperature resistant magnet material.
If you want to buy a permanent magnet with an operating temperature between 250°C and 350°C, it is recommended that you choose samarium cobalt magnets. This magnet is ideal for working at temperatures of 250°C-350°C.
However, if you are buying permanent magnets that operate below 300°C, ferrite magnets are a good choice. The upper limit of the operating temperature of ferrite magnets is 300°C.
However, if you want to find a permanent magnet suitable for the working temperature of 80℃-230℃, it is recommended that you choose NdFeB. This magnet is suitable for the working temperature of 80℃-230℃ and has strong magnetic force.
2. Magnetic force (from strong to weak)
NdFeB magnets.
NdFeB magnets are the third generation of rare earth permanent magnet products and are currently the most powerful magnets. They are called strong magnets, or the king of magnets by people. Their (BH)max can reach 52MGOe.
Samarium cobalt magnet.
The magnetic force of samarium cobalt magnet is weaker than that of neodymium iron boron magnet. However, samarium cobalt magnets are easier to process into shaped magnets. Its (BH)max is about 26 MGOe.
Alnico magnets.
The magnetic force of an alnico magnet is weaker than that of samarium cobalt magnet, and its (BH) max is only 5.4MGOe. 4. Ferrite magnet. Among the four types of permanent magnets, we mentioned in this article, the ferrite magnet has the weakest magnetic force, its (BH)max is only 3.6 MGOe.
3. Magnet price (low to high)
Ferrite magnet.
Because the raw materials of ferrite magnets are relatively cheap, the price of ferrite magnets is very low, and their market demand is very large, mainly used in handbag factories, speaker factories, leather products factories.
NdFeB magnets.
Although the annual output of NdFeB magnets is less than that of ferrite, NdFeB magnets are cost-effective and have the highest output value. They are involved in various industries, mainly used in magnetic connectors, DC motors, robots, smart home and other fields.
Alnico magnets.
AlNiCo is the earliest developed permanent magnet material, which is an alloy composed of aluminum, nickel, cobalt, iron and other trace metal elements. Such magnets are relatively expensive and are mainly used in motors, microphones, sensors, speakers, traveling wave tubes, etc.
Samarium cobalt magnet.
Samarium cobalt magnet is a magnetic material made of samarium, cobalt and other rare earth metals by mixing, smelting and refining into alloys, grinding, pressing and sintering. The cost of producing samarium cobalt magnets is very high. This type of magnet is only used in some high-end permanent magnet motors.
Hope the above can help you choose the right magnet.