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Abstract: In the present paper the influence of RE alloying additions (Y, Gd, Tb and Dy) on magnetic properties (Curie temperatures, low temperature magnetization, zero field cooling–field cooling curves, domain structure, room temperature magnetostriction and magnetic permeability) of amorphous alloys of type Fe82Nb2B14RE2 are carefully examined. It was shown that substituting of yttrium atoms by magnetic elements, i.e. Gd, Tb and Dy leads to (i) an increase of the Curie temperature of amorphous phase from 416K (for Fe82Nb2B14Y2) to 450K (for Fe82Nb2B14Gd2) and (ii) a decrease of magnetization in saturation (magnetic field 7T) which can be explained by antiferromagnetic Fe–RE coupling resulting in a decrease of magnetic moment calculated per magnetic atom from 2.00μB for the Fe82Nb2B14Y2 alloy (Fe in amorphous phase) to 1.51μB for the Fe82Nb2B14Tb2 alloy. It was concluded that Tb and Dy alloying additions introduce a local magnetic anisotropy responsible for significant decrease of initial magnetic permeability (about 5 times in relation to Fe82Nb2B14Y2 or Fe82Nb2B14Gd2 alloy), increase of magnetic irreversibility effect measured at 2K (about 10 times in relation to the same alloys) and appearing of the finger-print magnetic domain regions (not observed for the Fe82Nb2B14Y2 and Fe82Nb2B14Gd2 alloys). [Copyright &y& Elsevier]

The short-range order in the liquid Al86 - xCo14Six (x = 4, 10, 12 at.%) alloys at 50, 150 and 250 °C above liquidus temperature has been studied by X-ray diffraction and reverse Monte Carlo simulations. The analysis of local atomic structure in RMC-models has been carried out by means of the Voronoi-Delaunay method. The existence of a prepeak on the total structure factor curves of the liquid alloys that identified medium range order caused by the specific arrangement of Co atoms has been observed. It was discovered that metastable CoSi intermetallic and nanocrystalline Al and Si phases have been formed in melt-spun Al74 Co14 Si12 alloy. The annealing of the melt-spun Al74 Co14 Si12 ribbons causes the attainment of Al9 Co2 and Si crystal phases. [ABSTRACT FROM AUTHOR]