Method for preparing soft magnetic material by using liquid nitrogen through high-speed ball milling
US11504767B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 2020 |
| Grant date | Nov 22, 2022 |
| Priority date | — |
| Expiry date | Nov 25, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F41/0246
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
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…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.