(Pr,Nd)-Fe-B nanocrystalline magnetic materials with TiC additions

The effect of titanium carbide (TiC) addition and Pr substitution in nanocrystalline Nd-Fe-B based magnetic materials has been investigated. Rapidly solidified (Pr,Nd)-Fe-B alloys were prepared by melt spinning. The compositions studied were ( Pr x Nd 1 − x ) 9.5 Fe 84.5 B 6 ( x = 0 , 0.1, 0.25, 0.5, 0.75, and 1) with the addition of 3 at. % TiC. Varying the wheel speed from 15 to 30 m ∕ s , the best magnetic properties were found for samples prepared at 20 m ∕ s . All samples were nanocrystalline in the as-cast state. The average coercive field ranged from 10.0 to 12.6 kOe and energy product from 7.8 to 9.0 MGOe . The improvement in the coercive field compared to similar Nd based alloys was about 30%. Rietveld analysis of x-ray data for the Pr 9.5 Fe 84.5 B 6 sample revealed that this material consists of approximately 70 wt. % of 2:14:1 phase and 30 wt. % of α - Fe . This result was confirmed by Mössbauer data analysis and is in agreement with compositions expected from the ternary phase diagram.