The invention relates to a rapid salt-bath nitridation method by applying a
magnetic field. The method comprises the following steps: washing, pre-oxidizing, melting nitridation basic salts, applying a
magnetic field to carry out nitridation, and washing. The method has the advantages that under the effect of a
magnetic field, domain rotation and domain wall displacement are generated around the material surface, the exchange energy and
anisotropy energy are increased, and the
nitrogen atom
diffusion is accelerated;
magnetization happens near the surface of workpiece,
magneto-striction is generated then, the
strain energy is increased, and the
diffusion of
nitrogen atom is accelerated;
active nitrogen atoms diffuse on the material surface under the effect of the magnetic field, the surface adsorption and
diffusion are accelerated, the penetration is promoted and accelerated, the salt-bath
nitrogen penetration time is reduced, the energy is saved, and the environment is protected; the
hardness and surface wear-resistant performance of a sample is improved, the excellent
surface corrosion resistant performance of the sample can be preserved; in the provided method, people can obtain a nitrogen penetration layer with the same thickness as that of a nitrogen penetration layer, which is produced by a common salt-bath nitrogen penetration method, by low-temperature heating, thus the energy is saved, and the production cost is reduced.