Many of our customers have such questions: What is the strongest magnet? How many types of magnets are there? If you are also puzzled by these questions, then you’ve come to the right place. In this article, we will give a list of magnets by strength and introduce them one by one.
Common permanent magnet magnets on the market mainly include NdFeB Magnet, SmCo magnet, AlNiCo magnet, and ferrite magnet. If these magnets are arranged according to their magnetic force from large to small, they are NdFeB magnet, SmCo magnet, AlNiCo magnet, and ferrite magnet.
1. NdFeB Magnet
NdFeB magnet is a tetragonal crystal composed of neodymium, iron and boron (Nd2Fe14B). It is also the most commonly used rare earth magnet. NdFeB magnets are widely used in electronic products, such as hard drives, mobile phones, earphones, and battery-powered tools.
NdFeB magnets are divided into sintered NdFeB magnets and bonded NdFeB magnets. Bonded NdFeB magnets are magnetic in all directions and resistant to corrosion while sintered NdFeB magnets are easily corroded, and their surface needs to be plated. Common coatings usually include zinc plating, nickel plating, and so on.
2. SmCo Magnet
SmCo magnet is another kind of rare earth magnet. It is a kind of magnet made by mixing samarium, cobalt, and other metals to form an alloy, and then the alloy is crushed, pressed, and sintered. It has a high magnetic energy product, a very low temperature coefficient, and a maximum operating temperature of 350°C.
It has strong corrosion resistance and oxidation resistance, so it is widely used in the aerospace, defense, and military industry, microwave devices, communications, medical equipment, instruments, meters, various magnetic transmission devices, sensors, magnetic processors, motors, etc. The maximum energy product (BHmax) of samarium cobalt magnets ranges from 16 MGOe to 32 MGOe, and its theoretical limit is 34 MGOe. SmCo magnets have two composition ratios, namely (samarium atom: cobalt atom) 1:5 and 2:17.
3. AlNiCo Magnet
AlNiCo magnet is an alloy composed of metal aluminum, nickel, cobalt, iron, and other trace metal elements. The composition of its metal components is different, the magnetic properties are also different, and the uses are also different. There are three different production processes for AlNiCo permanent magnets: casting, sintering, and bonding. The casting process can be used to process and produce magnets of different sizes and shapes. Compared with the products produced by the casting process, the product produced by the sintering process has a smaller size, and the rough product produced by this process has a small dimensional tolerance and good casting machinability.
Among permanent magnets, cast AlNiCo permanent magnets have the lowest reversible temperature coefficient, and the working temperature can be as high as 500 degrees Celsius.
4. Ferrite Magnet
Ferrite magnets are permanent magnets mainly made of SrO or BaO and Fe2O3. Compared with other permanent magnets, ferrite magnets are hard and brittle and have lower magnetic energy. However, it is not easy to demagnetize, not easy to be corroded, and the production process is simple and low in price. Therefore, ferrite magnets have the highest output in the entire magnet industry and are widely used in industrial production.
Thank you for reading our list of magnets by strength and we hope it can help you to have a better understanding of permanent magnets. If you want to learn more about magnets, we would like to advise you to Stanford Magnets for more information.
As a leading magnet supplier across the world, Stanford Magnets has been involved in R&D, manufacturing, and sales of magnets since the 1990s. It provides customers with high-quality permanent magnets like SmCo magnets, neodymium magnets, AlNiCo magnets, and ferrite magnets (ceramic magnets) at a very competitive price.