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NdFeB magnet is mainly made of Neodymium, lron, Boron and other metals together, lt has the high remanence, high coercive force , high energy product and high performance/cost ratio.The magnets are mainly used in PM motors , loudspeaker, meters, medical instruments, magnetic separators and other fislds.The surface treatment method includes Zn, Ni, Tin, Gold, Silver plating, phosphate and Epoxy resin ect.