METHOD FOR THE PRODUCTION OF PERMANENT MAGNETS AND A PERMANENT MAGNET

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Provided is a method for the production of permanent magnets whereby permanent magnets having effectively improved or restored magnetic characteristics such as coercive force which are corrosion resistant and weather resistant can be produced at low cost and in a way which is suitable for mass production. An iron - boron - rare earth sintered magnet and a metal vaporization material which contains at least one of Dy and Tb are arranged in a treatment chamber and heated to vaporization. An inert gas is introduced into the treatment chamber where the sintered magnet has been arranged while the metal vaporization material is being vaporized. Metal atoms are deposited while the quantity of vaporized metal atoms being supplied to the surface of the sintered magnet is adjusted by controlling the partial pressure of the inert gas and the metal atoms are diffused into the crystal grain boundaries and/or crystal grain boundary phase of the sintered magnet before a thin film comprised of deposited metal atoms is formed. Cold gas is then introduced into the treatment chamber where the sintered magnet has been arranged and a reaction gas is introduced while the treatment chamber is being cooled, and the surface of the sintered magnet is covered with a reaction film and set in a fixed state.