Non-rare earth magnets have a long history, and their mass production and industrial application in the middle of the 20th century gradually matured. It was not until the late 20th century that rare earth magnets emerged with the development of powder metallurgy technology that non-rare earth magnets were distinguished from them.
Rare earth magnets are made of rare earth elements and ferromagnetic elements. They can generate a strong magnetic field and have excellent coercive force. Its magnets are brittle and easy to crack, and are susceptible to corrosion loss. Therefore, other metals are generally used as their coatings to protect rare earth magnets.
Common rare earth magnets include: cobalt-samarium magnets developed in the 1970s, which were the first mass-produced rare earth magnets; and nowadays mainstream neodymium iron boron magnets were put on the market in 1984.
Non-rare earth magnets, such as iron oxide and AlNiCo magnets, are relatively simple and cost-effective, and do not need to rely on rare earth ore raw materials for production.