Structure studies of Fe81Nb5B14 annealed alloys by Rietveld refinement
University of Silesia, Institute of Material Science, Bankowa 12, Katowice 40-007, Poland
The amorphous Fe81Nb5B14 alloys were obtained by melt spinning method as ribbons of 10 mm width and 25 μm thickness. For the creation of the nanocrystalline structure the alloys were annealed at the temperature range of 300 to 1025 K. The amorphous state was observed till temperature of 730 K. After annealing at 760 K the creation of the nanocrystalline solid solution based on α-Fe structure was observed. The full crystallization of α-Fe and borides (Fe2B and Fe3B) was observed after annealing at temperature of 1025 K.
The amorphous alloys were analysed by the Radial Distribution Functions in case of the coordination radii calculation. The analysis has shown that the basic type of order is typical for α-Fe model structure.
Both, the amorphous and the nanocrystalline alloys were analysed by the Rietveld refinement. In case of the amorphous material the modificated model of the solid solution structure based on α-Fe was used. The determination of the lattice parameter of structure model was the result of the refinement (3.0491 Å to 2.9639 Å). In case of the nanocrystalline alloys on the X-ray patterns were observed diffraction lines typical for α-Fe (2.8748 Å – 2.8655 Å). The lattice parameter of α-Fe after crystallization was 2.8644 Å. The values of the received Rietveld refinement parameters were in the ranges of Rwp = 7 – 21 %, Rp = 5 – 16 %, Rexp = 5 - 20% and S = 1.09 – 1.58.
Presentation: poster at E-MRS Fall Meeting 2005, Symposium B, by Małgorzata Karolus
See On-line Journal of E-MRS Fall Meeting 2005
Submitted: 2005-05-24 15:19 Revised: 2009-06-07 00:44