Abstract: The carbides of NdDy0.2Fe12-yMoyC0.6 (y=1.5, 2) crystallized in the ThMn12-type structure have been successfully synthesized by arc melting method, followed by a heat treatment. The magnetic properties are strongly enhanced with the addition of carbon. Upon the carbonation the saturation magnetization Ms is increased by about 20emu/g and the Curie temperature Tc is enhanced by 40--70K. The spin reorientation (SR) temperature decreases from 125 K for NdDy0.2Fe10Mo2 to 55 K for NdDy0.2Fe10Mo2C0.6 indicating the change of magnetocrystalline anisotropy in the Nd sublattice. It is found that the intrinsic magnetic properties of the carbides can be improved by further nitrogenation. The composite carbon--nitrogen compounds show a Tc~560K, Ms~105emu/g and Ha (anisotropy field) ~86kOe for NdDy0.2Fe10Mo2C0.6Nz and a Tc~628K, Mx~119emu/g and Ha~115kOe for NdDy0.2Fe10.5Mo1.5C0.6Nz. These magnetic properties are even better than those of simple nitrides, suggesting that these compounds can be considered as a good candidate for permanent magnet applications.
LIU Shun-Quan;HAN Jing-Zhi;DU Hong-Lin;WANG Chang-Sheng;YANG Ying-Chang. Magnetic Properties of Melted ThMn12-Type Carbides and Their Nitrides[J]. 中国物理快报, 2006, 23(8): 2229-2231.
LIU Shun-Quan, HAN Jing-Zhi, DU Hong-Lin, WANG Chang-Sheng, YANG Ying-Chang. Magnetic Properties of Melted ThMn12-Type Carbides and Their Nitrides. Chin. Phys. Lett., 2006, 23(8): 2229-2231.