With the development of society, the application of magnets are increasingly being used, from high-tech products to the most simple packaging and magnetic, is currently the most widely used Or NdFeB

magnets and Ferrite magnets. From the magnet's development history, the late nineteenth and early twentieth centuries, people mainly use carbon Steel, tungsten steel, chrome steel and cobalt steel for permanent magnets. The late thirties the twentieth century, aluminum, nickel and

cobalt magnets successfully developed, it should be to make a large-

scale magnets
    With the possible. The fifties, the emergence of barium ferrite magnets, permanent magnet not only reduces the cost of permanent magnetic materials in turn broaden the scope of application to the
High-frequency field. To the sixties, the emergence of samarium cobalt permanent magnet, for the magnet application opens a new era. In 1967, the United States Dayton University of Strnat and so on, for the development of samarium cobalt magnet, rare earth magnet marks the era. To date, thin permanent magnet 10 has experienced first-generation SmCo5, second-generation precipitation hardening Sm2Co17, developed to the third generation of Nd-Fe-B permanent magnetic materials. Currently the largest amount of ferrite magnets is still
    Permanent magnet materials, NdFeB magnets, but the output has been much higher than the ferrite permanent magnet materials, NdFeB magnet production has developed into a major industry for