Developed in 1982 by General Motors and Sumitomo Special Metals, neodymium magnet known as NdFeB, NIB or Neo magnet is the most widely used type of rare-earth magnet due to its strongest magnetic adhesive force. It is a permanent magnet made from an alloy of neodymium, iron and boron to form the Nd2Fe14B tetragonal crystalline structure. Neodymium magnet is the super-strong type of permanent magnet and even it in small piece still can create effective magnetic force. Neodymium magnet is used widely in many applications like electrical motors, hard disk drives, audio equipment and magnetically coupled pumps. Read More
Samarium Cobalt was the first rare-earth transition-metal magnet to be developed. It was a quantum leap in energy product and made it possible to put a large amount of stable flux in a small package.
SmCo5 and Sm2Co17 have low temperature coefficients and chemically stable. SmCo is very hard and fragile: if you drop it, it will break.