Effects of Ti Addition on Microstructure and Magnetic Properties of B-rich Nd9.4Fe79.6-xTixB11 Nanocrystalline Alloys

The effects of Ti addition on the microstructure and magnetic properties of Nd9.4Fe79.6-xTixB11(x=0, 1, 2, 4, 6) nanocrystalline alloys were investigated. The results show that Ti addition suppresses the formation of unfavorable soft Nd2Fe23B3 and Fe3B phases, and promotes the formation of Nd2Fe14B phases. When the Ti content reaches a certain amount, Ti may precipitate as TiB2 from the alloys. TiB2 may serve as inoculants and promotes uniform nucleation, and thus increases the exchange coupling between the hard and soft phases. As a result, excellent magnetic properties of Br=0.87 T, Hcj=931 kA/m and (BH)max=115.4 kJ/m3 are achieved in Nd9.4Fe75.6Ti4B11 alloy ribbons.