Patent ID: 11504767

Abstract:
The disclosure discloses a method for preparing a γ′-Fe4N soft magnetic material by using liquid nitrogen through high-speed ball milling, and belongs to the field of the soft magnetic material. According to the method of the disclosure, high energy in the liquid nitrogen is used for obtaining a nanometer material FexN with a nitrogen atom supersaturation degree through cryogrinding. At a low temperature, the material is very brittle, and a surface volume ratio is very high, so that a content of nitrogen atoms adsorbed on a surface of a sample is as high as 22%. Through 300° C. post-annealing, γ′-Fe4N is directly obtained from α-Fe through phase change, so that a nanometer crystal γ′-Fe4N soft magnetic material is prepared. The method of the disclosure has the advantages that an operation is simple and convenient, the cost is low, the large-scale industrialized production can be realized, and the method belongs to a novel alternative method for preparing a high-grade soft magnetic material with ideal magnetism. The γ′-Fe4N soft magnetic material prepared by the method of the disclosure has the advantages of high Ms, low coercivity and high surface resistivity, and can be used for a transformer and an inductor operated in a high-frequency semiconductor switch.