Sintered SmCo Magnet Grades

Samarium cobalt (SmCo) magnets include 1:5 type (SmCo5) and 2:17 type (Sm2Co17) magnets. Both types of SmCo magnet grades basically include three parts, i.e. “letter 1” + “number” + “letter 2”. The three parts in sintered SmCo magnet grades present material type, (BH)max value (in CGS unit) and Hcj level, respectively. The part “letter 1” are “XG” and “XGS” for sintered SmCo5 and Sm2Co17 magnets, respectively. Besides, the Hcj levels of sintered SmCo5 magnets include “default” (Hcj ≥ 15 kOe) and “H” (Hcj ≥ 23 kOe) and those of sintered Sm2Co17 magnets include “L” (Hcj ≥ 8 kOe), “M” (Hcj ≥ 12 kOe), “default” (Hcj ≥ 18 kOe), “H” (Hcj ≥ 25 kOe) and “LT” (Hcj ≥ 18 kOe). Although the Sm2Co17 magnet grades with the right part “default” and “LT” have same Hcj level, they contain different meanings in the aspect of temperature coefficient of remanence α(Br). The grades with “LT” mean that the corresponding magnets have low/near zero |α(Br)| compared to the others without “LT”.