The Alnico magnet is a high properties permanent magnetic material. It is formed by metal Al,Ni,Co,Fe and some other metal elements. According to the manufacture method,the Alnico magnet can be divided into sintered and cast. The cast Alnico magnet can be produced into all kinds of size and dimension. The magnetic property is very high,lower of reversible temperature coefficient. The sintered Alnico magnet is only can be produced into small specification,but the mechanism intensity of the sintered Alnico magnet is stronger the cast one.