Speaker, compass, door seal on refrigerator door, door suction, magnetic levitation train, induction cooker, magnetic needle, telephone, mobile phone, magnetic jewelry, magnetic toys, leather cases and bags, making motors, generators (cutting magnetic induction wire to generate electricity), cranes, bells and so on. Magnet type magnets can be classified as "permanent magnets" and "non-permanent magnets". Permanent magnets can be natural products, also known as natural magnets, or they can be manufactured artificially (the strongest magnet is a neodymium magnet). A non-permanent magnet, however, has magnetism only under certain conditions, usually in the form of an electromagnet, which uses an electric current to strengthen its magnetic field.
Metallic alloy magnets include NdFeB (Nd2Fe14B), SmCo, ALNiCO. Ferrite.
1, NdFeB magnet: it is currently found commercial performance of the highest magnet, known as king of the magnet. Having extremely high magnetic properties, its maximum magnetic energy product (BHmax) is more than 10 times higher than Ferrite. Its own mechanical processing performance is also quite good. Working temperature up to 200 ℃. And its quality of a material is hard, performance is stable, have very good cost performance, its application is extremely extensive. However, because of its strong chemical activity, it need to make a protection coating one the surface. (such as Zn,Ni, electrophoresis, passivation, etc.).
2. Ferrite magnet: its main raw materials include BaFe12O19 and SrFe12O19. It is made by ceramic technology, which is hard and brittle. Because ferrite magnet has good temperature resistance, low price and moderate performance, it has become the most widely used permanent magnet. Ferrite magnets can also be bonded, made in to Flexible magnets, flexible magnets is widely used in sign industry and printing industry.
3. ALNiCO magnet: it is an alloy composed of aluminum, nickel, cobalt, iron and other trace metal elements. Casting process can be processed into different sizes and shapes with good machinability. Casting aluminum nickel and cobalt permanent magnet has the lowest temperature coefficient is reversible, working temperature can be as high as above 600 ℃. Alnico permanent magnet products are widely used in various instruments and other applications.
4. SmCo is divided into SmCo5 and Sm2Co17 according to different components. Its development was limited by the high cost of its materials. As rare earth permanent magnet, SmCo has high magnetic energy (14-28 mgoe), reliable coercivity and good temperature characteristics. Samarium cobalt magnets work better at high temperatures than ndfeb magnets