A magnet that can maintain its magnetism for a long time is called a permanent magnet. There are many types of such magnets on the market today, such as neodymium magnets, SmCo magnets, AlNiCo magnets, and Ferrite magnets. And every type of permanent magnet has a unique set of characteristics that can affect how it performs in various applications. For many people, especially those who are new to magnets, it is really difficult to choose a proper permanent magnet that can satisfy their daily use. So in this article, we will introduce how to choose a permanent magnet in detail.
3 Key Parameters to Consider When Choosing a Permanent Magnet
1. Use of Temperature
When choosing a permanent magnet, one of the most important parameters is the temperature of use.
If you want to choose a permanent magnet with an operating temperature of 500°C, we recommend that you choose Alnico magnets. It can withstand an operating temperature of 500°C and is the most temperature-resistant magnet material.
If you want to buy a permanent magnet whose operating temperature is between 250°C and 350°C, we recommend that you choose SmCo magnets. It is ideal for this magnet to work between the temperature of 250℃-350℃.
However, if you want to purchase a permanent magnet with an operating temperature below 300°C, ferrite magnets are a good choice. The upper limit of ferrite magnets’ operating temperature is 300℃.
But if you want to find a permanent magnet suitable for an operating temperature of 80℃-230℃, we recommend that you choose NdFeB. This kind of magnet is suitable for an operating temperature of 80℃-230℃, with a strong magnetic force.
2. Magnetic Force (from Strong to Weak)
No. 1. NdFeB magnet. NdFeB magnets are the third generation rare earth permanent magnet products and are currently the most powerful magnets. They are called strong magnets, or king of magnets by people. Their (BH)max can reach 52 MGOe.
No. 2. SmCo magnet. The magnetic force of the SmCo magnet is weaker than that of the NdFeB magnet. However, SmCo magnets are easier to be processed into special-shaped magnets. Their (BH)max is about 26 MGOe.
No. 3. Alnico magnet. The magnetic force of Alnico magnets is weaker than that of SmCo magnets, and their (BH)max is only 5.4 MGOe.
No. 4. Ferrite magnet. The magnetic force of ferrite magnets is the weakest among the four types of permanent magnets we’ve mentioned in this article, and their (BH)max is only 3.6 MGOe.
3. Price (from Low to High)
No. 1. Ferrite magnet. Due to the raw materials of the ferrite magnets are relatively cheap, the price of ferrite magnets is very low, and their market demand is very large, mostly used in handbag factories, speaker factories, leather goods factories.
No. 2. NdFeB magnet. Although the annual output of NdFeB magnets is not as large as ferrite, NdFeB magnets are cost-effective and have the highest output value. They are involved in all walks of life, mostly used in magnetic connectors, DC motors, robots, smart homes, and other fields.
No. 3. Alnico magnet. 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 mostly used in motors, microphones, sensors, speakers, traveling wave tubes, and so on.
No. 4. SmCo magnet. SmCo magnet is a kind of magnetic material made of samarium, cobalt, and other rare earth metals by mixing, melting, and refining into the alloy, grinding, pressing, and sintering. The cost of producing samarium-cobalt magnets is very high. Such magnets are only used in some high-end permanent magnet motors.
Thank you for reading our article and we hope it can help you know how to choose a permanent magnet. If you want to know more about permanent magnets, we advise you to visit Stanford Magnets for more information.
Stanford Magnets is a leading magnet supplier across the world who has been involved in R&D, manufacturing, and sales of magnets since the 1990s. It provides customers with high-quality rare earth permanent magnetic products, and other non-rare earth permanent magnets at a very competitive price.