Structural and magnetic properties of R2Fe14−xTxB (R=Nd, Y; T=Cr, Mn, Co, Ni, Al)

Abstract
Trends in structural and magnetic parameters are presented and discussed for Nd2Fe14−xTxB with T=Cr, Mn, Co, Ni, Al. Some data are also included on the Y analog systems. Partial Al substitution strongly increases c/a. We show that this has to do with preferential occupation of the larger atom (Al) in the σFe layer. Co and Ni substitutions increase Curie temperature (TC) while all others decrease it. Anisotropy constants K for 300 K decrease in all cases investigated compared to Nd2Fe14B. Some discussion is given to the general mode of preferential substitution and the concomitant effects on magnetic anisotropy.