Crystal Structure and Phase Relations of the R2Fe14B-Y2Fe14B (R = Nd and Pr) Systems

摘要

The phase relations in the R2Fe14B-Y2Fe14B (R = Nd and Pr) systems have been investigated by means of X-ray powder diffraction (XRD), differential thermal analysis (DTA), and scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS). Crystal structure parameters for all studied alloys (R1-x Y (x) )(2)Fe14B (R = Nd and Pr) have been determined by Rietveld refinements. Their structures are similar to that of the Nd2Fe14B phase with tetragonal structure (space group P4(2)/mnm). The continuous solid solutions are formed in these systems. The lattice parameters and unit cell volumes of the (R1-x Y (x) )(2)Fe14B (R = Nd and Pr) solid solutions decrease gradually with increasing Y content. The DTA results present that the decomposition temperature of (R1-x Y (x) )(2)Fe14B (R = Nd and Pr) rises with x ranging from 0 to 1.0. The vertical sections of the R2Fe14B-Y2Fe14B (R = Nd and Pr) systems are presented in this work.