Neodymium iron boron (NdFeB) offers the highest Br and Hci values, it generates the highest energies among all permanent magnets, such as samarium cobalt magnets. The NdFeB magnet is therefore used in many applications, including green energy, brushless DC motors, magnetic separation, loudspeakers and security systems for the sport of cycling.
NdFeB magnets have some limitations due to their corrosive behavior. In humid applications, a protective coating is highly recommended. Coatings which have been used successfully include epoxy coating, nickel plating and combinations of these coatings. Parylene coating is one of the coatings and can be applied to magnet for medical area. The maximum operating temperature depends on the magnet's dimensions and its final applications.