Thermal evolution of Fe65Ni20Nb6B9 nanocrystalline metastable alloy

P. MENDOZA ZÉLIS; C. RODRIGUEZ TORRES; F. A. CABRERA; M. FERNÁNDEZ VAN RAAP; G. A. PASQUEVICH; F. H. SÁNCHEZ; A. GONZALEZ; J.J. SUNYOL

JOURNAL OF METASTABLE AND NANOCRYSTALLINE MATERIALS

Año: 2004 vol. 20 p. 571 - 575

1422-6375

The alloy Fe65Ni20Nb6B9 was obtained from the elemental constituents in a high-energyplanetary ball mill and was studied by 57Fe Mössbauer effect spectroscopy, Mössbauer thermalscans and X-ray diffraction. The as prepared nanocrystalline alloy consisted primarily of metastablebcc a-Fe(Ni) nanocrystals (57 nm average size) and small amounts of g-(Fe,Ni) with Niconcentration of about 58%. Up to about 693 K only defect recovery is inferred. Between 693 and873 K the a-phase transformed gradually into the fcc g-phase, whose starting Ni concentrationdecreased continuously with increasing temperature, reaching a final value which was below 32 at.%