Enhanced thermal stability of sintered (Nd,Dy)(Fe,Co)B magnets by the addition of Ta or Ti

The addition of 2 at% Ta or 1 at% Ti into a (Nd,Dy)-(Fe,Co)-B alloy is very effective in improving room temperature coercivity and thermal stability. The Ta containing alloy showed 30 % higher coercivity value than that of Ta-free alloy at temperatures higher than 100 degrees C. Both Ta and Ti alloying greatly reduced the high temperature reversible losses at temperatures of up to 225 degrees C. They are thus potential in high temperature applications.