Large-scale production and magnetic properties of Sn-substituted MnBi rare-earth-free melt-spun ribbons
摘要
The effects of Sn dopant on microstructure and magnetic properties of large-scale produced MnBi1 − xSnx (x = 0; 0.05; 0.10; 0.15; 0.20; 0.25) melt-spun ribbons were systematically investigated. With increasing Sn content, the MnBi LTP fraction within the produced ribbons exhibited a decreasing trend, associated with the formation of the Mn3Sn phase. The doped Sn atoms also affected the quenching process, altering the ribbons’ microstructures from the grain-like to rod-shaped. The optimized composition was found to be MnBi0.95Sn0.05, which was used to fabricate MnBi-based magnets. Maximum energy products of 12.9 MGOe, 8.1 MGOe, and coercivities of 14.8 kOe, 6.7 kOe were obtained for the MnBi0.95Sn0.05 melt-spun annealed ribbons and magnets prepared from them, respectively.