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The temperature dependence of wettability (wetting angle, Θ(T )) for Ag-based melts on graphite and Al2O3 substrates is compared. Typical alloying e ects are found, as the Ag host metal is gradually replaced by various metallic elements. The essence of alloying lies in the change of the electron/atom (e/a) ratio. This ratio is also manifested in the shift of wetting angles on the same substrate. The e ect is also supported by the calculations based on the rigid band model, and is also in qualitative agreement with the Hume-Rothery rules. Nevertheless, the e ects are partially smeared by other (metallurgical) factors, like the interaction between the oxygen-alloying elements and by the graphite substrate oxygen interaction. In contrast, such e ects are not pronounced in the case of Al2O3 substrates. As a consequence, Θ(T ) exhibits an opposite trend in the case of two substrates. Crossovers of the Θ(T ) curves were often found. The positions of crossovers depend on the chemical character and concentration of solute atoms. Segregation and epitaxial texture formation after solidi cation were also observed in certain alloy drops, especially in high concentration range. This phenomenon is not yet explained in every detail. DOI: 10.12693/APhysPolA.124.78

A non-monotonic compositional dependence of the amorphous Curie temperature (T am c ) and of the thermopower (S) was found in Fe80−xCrxB15 glassy samples. The significant change in the slope of concentration dependence of both properties lead to the conjecture of a hidden structural change in amorphous state. Similar anomalies were also observed earlier in the concentration dependence of microhardness in the same glasses, which clearly contradicts to the traditional homogeneous single phase concept of glassy state. The results are interpreted on the basis of the existence of quenched-in phase reminiscences (clusters) in these alloys inherited from the liquid state.

In Fe based glasses not solely the stress-sensitive magnetic properties, but also the amorphous Curie temperature (T am C ) can be altered by hydrogen absorption or due to the low temperature “heat treatments” in liquid N2 (−196◦C). The sign and magnitude of this T am C shift is strongly compositional dependent, but it is also influenced by the thermal history of glasses (heat treatments). In this paper new experimental results are presented, which were obtained on FeCrB alloys, supporting the previous observations. An attempt of interpretation of the results is also made, which is based on the existence of the quenched-in phase reminiscences, being inherited from the liquid structure.

The possible origin of short range atomic displacements coupled with the irreversible amorphous Curie temperature relaxation (∆T am C ) in Fe-based glasses is discussed and analyzed on the basis of quenched-in phase reminiscences. The displacements are dominantly symmetry changes, which are governed by the relative stability of fcc and bcc quenched-in phase reminiscences at a given temperature range. Those of elements which cause positive ∆T am C in as quenched state, also cause positive irreversible ∆T am C during structural relaxation. The influence of Cr addition is just the opposite in this respect.

Thermoelectric power and surface magnetic characterization of Ni evaporated layers will be presented, with the comparison with the bulk Ni material. The bulk electrical and magnetic properties are developed gradually, approaching the bulk properties, as the layer thickness increases. Below the thickness of 180 nm, the evaporated layers are amorphous. The epitaxial stresses can appear in both, the anomaly observed in the thermopower and the surface coercivity measurements.

In this contribution a less common experimental procedure is presented, which includes simultaneous application of electrical pulse heating, and longitudinal mechanical stress, applied along the ribbon length, for the magnetic property tailoring. The annealing is performed in protecting atmosphere in a vertical tube furnace by applying a weight at the free, cold bottom end of the ribbon. In these circumstances neither nanometer-size grains nor the concentration-distribution have been developed. The static coercive force, anisotropy and demagnetizing factor are monitored as a function of pulse number.

The change of thermopower is investigated in Fe-based glassy alloys during structural relaxation and amorphous-crystalline transformation. It was found, that thermopower shifts to negative direction until solely the relaxation proceeds. This negative shift is composition independent. The net shape of thermopower curves is composed from the thermopower of the individual constituent crystalline phases after the crystallization process.