X-RAY-DIFFRACTION STUDIES OF NI-CR-BASED AMORPHOUS-ALLOYS

The structures of the amorphous alloys with atomic percent compositions Ni68.21Cr14.22P17.22C0.35 (MBF 65) and Ni67.33Cr14.31B18.11C0.25 (MBF 80), which have similar Ni–Cr–C components, have been studied and compared by X-ray diffraction. The interference functions, atomic distribution functions, and radial distribution functions were calculated from the X-ray diffraction intensity data. The nearest-neighbor distances and coordination numbers were determined to be 2.52±0.01 Å, 12.50±0.10 for MBF 65, and 2.48±0.01 Å, 12.75±0.11 for MBF 80, respectively. The observed nearest-neighbor distance is in good agreement with a simple contact-distance packing model using the calculated atomic radii and a coordination number of twelve. These results are compared with the same composition of Ni in amorphous Ni–P and Ni–B alloys. © 1990 The Japan Society of Applied Physics.