SmFeN samarium ferrite magnet

- Dec 26, 2020-

SmFeN samarium ferronitrogen magnet refers to R2Fe17Nx or R2Fe17NxH ternary or polymetallic intermetallic compounds formed by R2Fe17 after nitride treatment. SmFeN permanent magnetic materials are the third generation permanent magnetic materials. Because SmFeN permanent magnetic material has excellent magnetic properties, but low Curie temperature, in some special applications, The NdFeb cannot meet. Based on the second generation of samarium and cobalt type permanent magnetic materials, the modified permanent magnetic materials can not only adapt to certain high temperature environment, but also further enhance their magnetic properties.


SmFeN samarium ferrite and nitrogen compound is thermodynamically unstable and begins to decompose above 600℃. Therefore, magnets cannot be made by traditional sintering process, but this alloy powder can be used to make bonding magnets. The alloy powders can be prepared by traditional powder making process, but the properties of the powders prepared by melt quenching or mechanical alloying method are better.


A rare earth permanent magnetic alloy based on Sm2Fe17 N2.3 intermetallic compound. In 1990, J. M. D.Coey et al. from Ireland found that Sm2Fe17 irreversibly absorbed a large amount of nitrogen through gas-solid reaction above 300℃. When nitrogen atoms enter Sm2Fe17, a new interstitial compound, SM2FE17n2.3, is formed, which not only increases the monocyte volume of Sm2Fe17 (about 3%), but also significantly increases the Curie temperature (Tc=476℃). Moreover, at room temperature there is a high saturation magnetization (Ms=1.54T) and a large anisotropic field, HA=14T. These are all important characteristics of excellent permanent magnet materials, which have aroused people's attention and research. Compared with Fecrco, Alnico, fecrco is superior in performance, but slightly weaker in temperature resistance and processable variability.