Abstract Scope |
The MnBi low temperature phase (LTP) is a promising permanent magnet material with theoretical maximum energy product (BH)Max 20 MGOe. The intrinsic coercivity (Hci) of LTP-MnBi exceeded 12 kOe and 26 kOe at 300 K and 523 K, respectively. LTP-MnBi has limitations. Obtaining with pure LTP-MnBi powders is difficult because of the drastic Mn-Bi peritectic reaction; Consolidating bulk magnet with high texture and full dense is difficult because of the 535K eutectic reaction of Bi and MnBi. Moreover, the saturation magnetization of MnBi is relatively low, less than 9 kG and 7 kG at 300 K and 523 K, respectively. To date, a bulk magnet with 11 MGOe and a composite film with 25 MGOe at 300 K have been fabricated. This talk reviews these efforts and highlights the important achievement, the key barrier that remains to be overcome, and possible approaches to optimize the properties for commercial applications. |