Samarium ferrite alloy has better corrosion resistance and can be compared with samarium cobalt alloy. Negative temperature coefficient of samarium iron nitrogen magnet alpha Br = 0.08% / ℃, between samarium cobalt (0.035% / ℃) and ndfeb alloy (0.12% / ℃), can be used under 200 ℃.
This is very beneficial for applications in automobile and other fields, because permanent magnets with good stability in the range of 150 ~ 200℃ need to be used in automobiles or motorcycles. These are the promising discoveries of samarium ferronitrogen alloys.
Since the nitrogen atoms in the sm2FE17n2.3 compound are absorbed by Sm2Fe17 at temperatures above 300 ° C, when the temperature rises above 550 ° C, the nitrogen atoms are removed from the SM2FE17n2.3 compound until they become Sm2Fe17. Therefore, it is very difficult to make completely compact sintered magnets, which can only be mixed with resin, plastic or low-melting metal to make bonding magnets, or made into hot-pressed magnets below 450℃.