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Neodymium-iron-boron (Nd-Fe-B) was discovered in 1983 and is currently the most powerful permanent magnet known to man. Nd-Fe-B is lighter and less expensive to produce than comparable permanent magnets, and the alloy is therefore capable of providing significantly more magnetic flux per unit weight or volume than any other permanent magnet available. Such advantages have provided a strong incentive for manufacturers to replace existing permanent magnet materials with Nd-Fe-B. Despite the potential benefits of employing the Nd-Fe-B magnet, however, its known susceptibility to corrosion has been cited as a problem with its use in many applications. Magnetic flux is dependent upon the volume of magnetic material present, and corrosive metal loss therefore directly decreases the power of a permanent magnet. If a substantial portion of a permanent magnet is lost due to corrosive dissolution, the magnet can eventually become incapable of performing its intended function. Many parts of industrial machines are exposed to potentially corrosive environments, and the technological impact of this new alloy may thu