The effect of alloying elements on the microstructure and properties of PrFeCoBNb sintered magnets produced using high energy milling

Abstract

An evaluation of the effect of alloying elements on the microstructure and magnetic properties of Pr15FebalCo8B7Nb0.05Mx (M = Al, Cu, P, Si, Gd, Ga, Dy or Tb; 0 ≤ x ≤ 0.5) sintered magnets has been carried out. A mixture of alloys and the high-energy milling technique have been used to prepare the magnets. The alloying elements have influenced the remanence, intrinsic coercivity and the squareness factor (SF). In general, Br has been reduced somewhat for the magnets with alloying additions. On the other hand, µ0iHc and SF exhibited some improvements compared to the standard composition Pr15FebalCo8B7Nb0.05 magnet, particularly SF. The concentration of the alloying elements showed no influence on the density of the magnets, which ranged between 97% and 99% of the theoretical value. Comparisons between the squareness factors obtained using the J×µ0H curve profile and the estimated using microstructural parameters have also been carried out.