Herein,we theoretically demonstrate that simple metal(Ga and Al)substitutional atoms,rather than the conventional transition metal substitutional elements,not only stabilize the ThMn_(12)-type SmFe_(12) and Sm(Fe,Co)_...Herein,we theoretically demonstrate that simple metal(Ga and Al)substitutional atoms,rather than the conventional transition metal substitutional elements,not only stabilize the ThMn_(12)-type SmFe_(12) and Sm(Fe,Co)_(12)phases thermodynamically but also further improve their intrinsic magnetic properties such that they are superior to those of the widely investigated SmFe_(11)Ti and Sm(Fe,Co)_(11)Ti magnets,and even to the state-of-the-art permanent magnet Nd_(2)Fe_(14)B.More specifically,the quaternary Sm(Fe,Co,Al)_(12)phase has the highest uniaxial magnetocrystalline anisotropy(MCA)of about 8 MJ m^(−3),anisotropy field of 18.2 T,and hardness parameter of 2.8 at room temperature and a Curie temperature of 764 K.Simultaneously,the Al and Ga substitutional atoms improve the single-domain size of the Sm(Fe,Co)_(12)grains by nearly a factor of two.Numerical results of MCA and MCA-driven hard magnetic properties can be described by the strong spin-orbit coupling and orbital angular momentum of the Sm 4f-electron orbitals.展开更多
基金This work is supported by the Future Materials Discovery Program(Grant No.2016M3D1A1027831)the Basic Research Program(Grant No.2020R1F1A1067589)through the National Research Foundation of Korea(NRF)the Ministry of Science and ICT and the Korea Institute of Energy Technology Evaluation and Planning(KETEP)grant funded by the Korea government(MOTIE)(Grant No.20192010106850,Development of magnetic materials for IE4 class motor).
文摘Herein,we theoretically demonstrate that simple metal(Ga and Al)substitutional atoms,rather than the conventional transition metal substitutional elements,not only stabilize the ThMn_(12)-type SmFe_(12) and Sm(Fe,Co)_(12)phases thermodynamically but also further improve their intrinsic magnetic properties such that they are superior to those of the widely investigated SmFe_(11)Ti and Sm(Fe,Co)_(11)Ti magnets,and even to the state-of-the-art permanent magnet Nd_(2)Fe_(14)B.More specifically,the quaternary Sm(Fe,Co,Al)_(12)phase has the highest uniaxial magnetocrystalline anisotropy(MCA)of about 8 MJ m^(−3),anisotropy field of 18.2 T,and hardness parameter of 2.8 at room temperature and a Curie temperature of 764 K.Simultaneously,the Al and Ga substitutional atoms improve the single-domain size of the Sm(Fe,Co)_(12)grains by nearly a factor of two.Numerical results of MCA and MCA-driven hard magnetic properties can be described by the strong spin-orbit coupling and orbital angular momentum of the Sm 4f-electron orbitals.
