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中文简体All the Neodymium Iron Boron, NdFeB, magnets are prone to corrosion (a method similar to rusting). They will require a form of protective coating. The standard coating is a triple-layer plating of Nickel-Copper-Nickel (Ni-Cu-Ni). This Ni-Cu-Ni coating is applied to the Neodymium Iron Boron magnets unless requested otherwise. It should be noted that the level of protection given by any coating depends on the environment the magnet will be subjected to and how the coating is looked after.
The magnetic output from the “Neo” magnet varies with temperature. The output falls with increasing temperature but usually returns as it cools (the degree of fall with rising temperature is dependent on the reversible temperature coefficients). It is possible to permanently reduce the magnetic output through too high a temperature (a permanent demagnetisation).
The level of permanent demagnetisation depends on the magnet shape, the total magnetic circuit and the actual shape of the BH curve (which will vary depending on the grade of “Neo” chosen). Neodymium Iron Boron, NdFeB, magnets are also affected by external demagnetisation fields and by radiation, both of which can demagnetise the magnet, the latter permanently demagnetising.
If the user understands the limitations of the NdFeB and their application, using NdFeB magnets can allow very compact designs with high-performance issues affecting the performance. For note, if the magnet is kept in dry conditions at all times and the plating is not broken and no external demagnetising fields are applied to it, the magnet theoretically can retain its magnetism indefinitely.
