The effects of various alloying elements on modifying the elevated temperature magnetic properties of sintered Nd-Fe-B magnets

Abstract
The effects of the alloying elements Co, Dy, Er, Al, and Nb on modifying the elevated temperature properties of sintered Nd-Fe-B–based permanent magnets have been studied in our laboratory. The results are summarized and analyzed. Small Nb additions increase coercivity and improve elevated temperature properties. Higher Nb additions lead to decomposition of the 2:14:1 phase into a 2:17 phase and a new magnetic phase with a Curie point around 350 °C. The effectiveness of Nb additions appears to be associated with the rare-earth content of the magnets.