EXTENDED X-RAY-ABSORPTION FINE-STRUCTURE STUDY ON AMORPHOUS ND-FE-B ALLOYS

The local structure and crystallization behavior of Nd15Fe77Bx (x = 2- 14) melt-spun alloys were studied by Nd L-3 extended x-ray absorption fine structure (EXAFS), The conventional x-ray powder diffractometry s tudies showed that the Nd-Fe-B melt-spun ribbons had the amorphous str ucture regardless of the boron content. EXAFS studies of the local str ucture around the Nd atom confirmed that the Nd-Fe-B melt-spun alloys had the amorphous structure and virtually the same nearest neighbor di stance from the Nd atom. The amorphous alloys were heated by a differe ntial scanning calorimetry in order to investigate the variation in th e local structure during the crystallization process by EXAFS measurem ents. Although no appreciable difference was found in the nearest neig hbor distance of the Nd atom between the amorphous alloys and the crys tallized alloys, the small variation in the nearest neighbor distance during the crystallization process was detected by EXAFS measurements.