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Co70 Fe8 Si9B13 amorphous ribbon, crystallized ribbon and a mixture of pure crystalline powders were mechanically alloyed by milling and nanocrystalline structures were obtained. The structural changes were monitored By X-ray diffraction and differential scanning calorimetry measurements. The thermal behaviour on heating the alloys prepared by ball milling was studied and the influence of the high-energy ball milling on the resulting phases was found.

Crystallization of amorphous Te-20 at. % Pb alloy obtained by rapid cooling from the liquid state was investigated by differential thermal analysis, X-ray diffraction and transmission electron microscopy. It was found that crystallization, beginning at 337 K, is of a continuous nature and proceeds over a fairly wide temperature range. At the first crystallization stage, nucleation of the metastable phase MS I, with hexagonal structure and lattice parametersa = 4.49 A andc = 5.85 A, takes place. Contrasts observed in the micrographs of single crystals of phase MS I were interpreted as areas with increased concentration of Pb atoms. With rising temperature, the phase present in these areas dissolves, and in its place platelet precipitates of the compound PbTe appear. In this paper, a sequence of decomposition for the amorphous phase obtained in the Te-20 at. % Pb alloy, as well as a model for the precipitation of PbTe, are proposed.

The paper presents the first results of studies on crystallization and domain structure of a new ferromagnetic amorphous alloy Co90Zr10. Amorphous Co-Zr alloys were obtained by the ″piston and anvil″ method with 20 to 45 at% of Co and 90 at% of Co. Crystallization of Co90Zr10 was studied by X-ray diffraction and differential calorimetry, as well as by transmission electron microscopy (TEM) with simultaneous heating of the material. Domain structure in the amorphous phase was investigated by the method of Lorentz. The types of structures occurring were described, domain wall widths were calculated, and the direction of changes in the parameters of the magnetic structure — caused by annealing and phase transformation — was suggested.

Crystallization of soft magnetic Fe-Si-B glasses was investigated by transmission electron microscopy and X-ray diffraction. Electron micrographs of the successive crystallization stages of some Fe-Si-B glasses were obtained and the morphology variations for different alloy compositions were determined. The compositional dependence of the crystallization mode exhibited by the Fe-Si-B glasses was analysed, and on this basis some suggestions about crystallization rules in these glasses are proposed. Two kinds of iron—silicon phases occurred, depending on the Fe-Si-B alloy composition: bcc Fe(Si) solid solution and an ordered solid solution on the structural basis of Fe3Si iron suicide. It is suggested that the metastable Fe3B phase (observed during crystallization of only few glasses) was not a simple consequence of boron content. Crystallization of the Fe3B phase was related to the formation of the iron—silicon phase which was produced during the first crystallization stage.

A supersaturated solid solution was obtained in an Sn-10 at. %Sb alloy rapidly quenched from the liquid state. Decomposition of this solution, taking place during isothermal annealing at 373 K, was investigated by transmission electron microscopy. In the first stage of decomposition, clustering of Sb atoms in definite planes of the tetragonal lattice of tin was observed. Subsequently, needle-like precipitates of the equilibrium compound SnSb were formed. The sequence of decomposition of the supersaturated solid solution Sn(Sb) and a model for the formation of the compound within the tetragonal lattice of tin are proposed.