Effects of Mn doping on structural and magnetic properties in NdFeB nanocomposites

摘要

The magnetic and structural properties of nanocomposite Nd_9Fe_(85-x)Mn_xB_6 (x= 0,0.5,1) have been investigated. It was found that the addition of manganese in the Nd_9Fe_(85)B_6 could promote crystallization and enhance the hard magnetic properties of the material. Thermomagnetic analysis (TMA) measurement indicated that the doping of Mn reduces the T_c of the Nd_2Fe_(14)B phase and raises that of alpha-Fe phase in the system. From the radial distribution curves around Fe atoms of Extended X-ray absorption fine structure (EXAFS), it has been demonstrated that for both the as-spun Nd_9Fe_(85-x)Mn_xB_6 (x=0,0.5,1) samples with lower x value and the annealed samples, the EXAFS curves appear to be similar to that of alpha-Fe.