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The high-entropy alloys (HEA) Al x FeCoNiCuCr (x  1.0, 1.5, 1.8) in cast state are investigated by means of X-ray diffraction, Mössbauer spectroscopy, magnetic and dilatometric methods. Two-phase state in the HEA and the increase of the crystal lattice parameter а of the f.c.c. and b.c.c. phases are detected. The decrease of the Curie temperature and the saturation magnetization upon deviation of Al content from equimolar composition are found out. Inhomogeneous magnetic order characterizes the studied HEA. For the studied HEA, the magnetic moment 0.2-0.4 B and the average thermal expansion coefficient <>  12.410 6 K 1 in the temperature range of 135-545 K are determined.

Electron microscopic and X ray diffraction methods have been used to study the fine structure of cast high entropy alloys (HEAs) Al x FeNiCoCuCr (x = 1, 1.5, 1.8). Disperse precipitates with dimensions of 130-400 and 10-20 nm have been revealed, the character of distribution of which, as well as the amounts, dimensions, and shapes, change with increasing aluminum content. In the equiatomic HEA, copper con taining particles with an fcc structure have been found; in the alloy with x = 1.8, particles of bcc Al 4 Cu 9 dom inate. It has been shown that the most uniform distribution over the matrix is characteristic of Co, unlike other elements, among which Cu and Cr are distributed in the alloy extremely nonuniformly and predomi nantly enter into the precipitated particles and into clusters in the interparticle spaces, respectively. Ni CrFe Co Fig. 4. Maps of the distribution of chemical elements over the volume of the region of the structure of the alloy А 3 shown in Fig. 3.

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The high-entropy alloy (HEA) AlFeCoNiCuCr in as-cast state and coating deposited on cooper and stainless steel substrates with the physical vapor deposition by cathode arc evaporation (PVD CAE) method was investigated using X-ray diffraction analysis and Mössbauer spectroscopy. Two fcc phases γ 1 and γ 2 and one bcc α-phase were detected in as-cast high-entropy alloys and in physical vapor deposition by cathode arc evaporation coatings. Mössbauer spectra consist of two kinds of components which belong to paramagnetic and ferromagnetic phases. The paramagnetic phases turn out predominantly in coating on cooper.Keywords: High-entropy alloy / Mössbauer effect / hyperfine magnetic fields / isomer shift Schlüsselwörter: Hochentropie-Legierung / Mößbauer Effekt / magnetisches Hyperfein-Feld / Isomerieverschiebung