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The results of the study of melting of Bi-Sn and Pb-Sn polycrystalline layered film systems with the thickness of 200-400 nm on a substrate with temperature gradient are given. Multilayer (each layer is of 10-20 nm) and bilayer films (layers are of 100-200 nm) of the same total thickness have been investigated. Broadening of the melting range in all films and lowering of melting point in multilayer samples compared to the bilayer ones have been observed. The observed phenomena are discussed within existing thermodynamic concepts in consideration of interfacial energy of contacting layers of components and energy of grain boundaries in polycrystalline films.

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Investigations of the penetration of hydrogen into ternary carbides (the so‐called MAX phases) become topical because it has been found recently that these materials can be protective coatings. Herein, near‐surface layers of two bulk samples of the Ti3AlC2 MAX phase are saturated electrolytically several times by hydrogen. Parameters of the hexagonal unit cell are measured by means of X‐ray diffractometry after each saturation of the same sample. It is found that the increase in the distance between the base planes of the unit cell is ten times larger than the increase of the side of the unit cell in the base plane. The estimated amount of hydrogen that remains in the lattice at room temperature is about 1.6% (at). It is found that the sample can be saturated by hydrogen up to 3% (at), but the lattice relaxes with time. The relaxation time for the distance between base planes is about 60% of that for the side of the lattice in the base plane.

The electrical resistivity of three samples is measured in the range 4.2–295 K. One sample contains the pure Ti3AlC2 MAX‐phase, and the other two samples contain this phase together with inclusions of TiC, TiO, and Al2O3 phases. To estimate the value of the residual resistivity of the TiC phase, data of energy‐dispersive X‐ray spectroscopy concentration distributions of elements are used. Estimations show that the Ti3AlC2 phase has the smallest residual resistivity of all phases and can electrically shunt other phases. The approximation of temperature dependences of the resistivity reveals that the Bloch–Grüneisen term of scattering of electrons on phonons (i.e., the term proportional to T5) increases strongly with the increase of volume fractions of inclusions. According to the proposed explanation of this effect, interstitial impurities of the carbon in the Ti3AlC2 phase migrate to neighbor crystals of the titanium carbide during the formation of the MAX phase, so the purification of this phase from carbon appears. As all other phases are electrically shunted by the Ti3AlC2 phase, the Bloch–Grüneisen term of the resistivity of this purified Ti3AlC2 phase increases.

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