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Amorphous Fe73B7Si16Nb3Cu1 ribbon was crystallized rapidly by electric current heating under simultaneously applied tensile stress along the ribbon axis. As a result, strong transverse magnetic anisotropy was induced in the ribbon. Dynamic magnetic properties of the ribbons rapidly heated either under the tensile stress or without tensile stress were measured using toroidal cores. Optimal electric current heating regime that provides maximum improvement of the initial magnetic permeability and core loss was determined. Tensile stress increase from 0 to 180 MPa was shown to result in the decrease of the initial magnetic permeability down to 400 and core loss at frequencies from 0.4 to 200 kHz. Comparative analysis of magnetic properties of the cut core (with non-magnetic gap) and the cores heated under tensile stress was carried out. The magnetic properties of the latter cores are advantageous for manufacturing the reactors and linear chokes of switch-mode power supplies.

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Amorphous Fe 73 B 7 Si 16 Nb 3 Cu 1 ribbon was crystallized rapidly by electric current heating under simultaneously applied tensile stress along the ribbon axis. As a result, strong transverse magnetic anisotropy was induced in the ribbon. Dynamic magnetic properties of the ribbons rapidly heated either under the tensile stress or without tensile stress were measured using toroidal cores. Optimal electric current heating regime that provides maximum improvement of the initial magnetic permeability and core loss was determined. Tensile stress increase from 0 to 180 MPa was shown to result in the decrease of the initial magnetic permeability down to 400 and core loss at frequencies from 0.4 to 200 kHz. Comparative analysis of magnetic properties of the cut core (with non-magnetic gap) and the cores heated under tensile stress was carried out. The magnetic properties of the latter cores are advantageous for manufacturing the reactors and linear chokes of switch-mode power supplies.

The phase equilibria in the Al-rich region of the {Y, Gd}-Ni-Al ternary systems at 773 K have been reinvestigated using XRD, microstructure and X-ray microprobe analysis. Four intermetallic compounds: 1-R 3 Ni 5 Al 19 (structure type Gd 3 Ni 5 Al 19), 2-R 4 Ni 6 Al 23 (Y 4 Ni 6 Al 23), 3-RNi 3 Al 9 (YNi 3 Al 9) and 4-RNiAl 4 (YNiAl 4), exist in both systems. It was shown that the thermodynamic equilibrium state of the samples could be reached after a relatively long heat treatment (up to four months). This is probably the main reason for some contradictions in the literature on the {Y, Gd}-Ni-Al phase diagrams. The crystal structure of the Y 3 Ni 5 Al 19 ternary compound (Gd 3 Ni 5 Al 19 type, space group Cmcm) was refined by the Rietveld method from powder X-ray diffraction data. The refined cell parameters are a = 0.40713(1) nm, b = 1.5957(3) nm, c = 2.7052(6) nm.