Adding ivabradine to carvedilol in patients with chronic heart failure improves the uptitration of β-blocker. The results merit further verification in a prospective double-blind study.

Titanium alloy product manufacturing is traditionally considered to be a rather difficult task. Additive manufacturing technologies, which have recently become quite widespread, can ensure the manufacture of titanium alloys products of an arbitrary geometrical shape. During this study, we have developed a methodology for manufacturing titanium alloys products using additive technologies on FL-Clad-R-4 complex of laser melting of metals by combined Selective Laser Melting (SLM) and Direct Metal Deposition (DMD) methods. Ti–6Al–4V and Ti–6Al–4Mo–1V alloys were used for the manufacture of samples. We studied the microstructure of the obtained details and measured the microhardness of the samples. We discovered a gradient of the structure throughout the height of the details walls, which is connected with the peculiarities of thermal cycles of the technology used. This affected the microhardness values: in the upper part of the details, the microhardness is 10–25% higher (about 500 HV) than in the lower part (about 400 HV). Products made according to the developed technique do not have visible defects and pores. The obtained results indicate the competitiveness of the proposed methodology.

Thermodynamic modeling of phase equilibria with the subsequent construction of the phase diagram of the SrO–Al2O3 system has been carried out. To calculate the activities of the oxide melt in the course of this work, we used the approximation of the theory of subregular ionic solutions, with the most optimal values of the energy parameters Q1112 = –104 349: Q1122 = –217 689; Q1222 = –104 436 J/mole. The results obtained for the liquidus line in this work are in good agreement with the literature experimental data. In the course of the calculation, the values of the equilibrium constants for the formation of strontium aluminates from the components of the oxide melt were estimated.

Over the past few years, interest in high-entropic alloys (HEAs) has been growing. A large body of research has been undertaken to study aspects such as the microstructure features of HEAs of various compositions, the effect of the content of certain elements on the mechanical properties of HEAs, and, of course, special properties such as heat resistance, corrosion resistance, resistance to irradiation with high-energy particles, magnetic properties, etc. However, few works have presented results accumulated over several years, which can complicate the choice of directions for further research. This review article presents the results of studies of the mechanisms of high-temperature oxidation of HEAs of systems: Al-Co-Cr-Fe-Ni, Mn-Co-Cr-Fe-Ni, refractory HEAs. An analysis made it possible to systematize the features of high-temperature oxidation of HEAs and propose new directions for the development of heat-resistant HEAs. The presented information may be useful for assessing the possibility of the practical application of HEAs in the aerospace industry, in nuclear and chemical engineering, and in new areas of energy.

The electrochemical behavior of as-cast AlxCoCrFeNiM (M = Ti, V, Si, Mn, Cu) high entropy alloys (HEAs) in 1 M NaCl and 0.5 M H2SO4 solutions is studied. Polarization measurements were carried out in a standard three-electrode electrochemical cell with a platinum auxiliary electrode using a P-30J potentiostat device. The potentials were measured relative to a saturated silver chloride reference electrode EVL-1M3 at room temperature (25 °C) with a sweep rate of 5 mV/s. It is shown that despite a wide passivation region, Al0.5CoCrFeNi1.6Ti0.7 HEA undergoes significant corrosion in both sodium chloride and sulfuric acid solutions and exhibits low corrosion potential and current density. Energy-dispersive X-ray spectroscopy (EDS) analysis revealed that Ti-containing eutectic areas are the most susceptible regions to corrosion. Intergranular corrosion was found in Al0.25CoCrFeNiMn and Al0.25CoCrFeNiCu HEAs. Moreover, Al0.25CoCrFeNiCu possesses the smallest passivation interval ΔE among all the investigated HEAs. For samples with Ti, Mn, and Cu, a protective film layer is not formed on the surface of the phases enriched in these elements, or it is brittle and crumbles. For samples with Si and V, a passivating film is formed. Thus, Al0.45CoCrFeNiSi0.45 and Al0.25CoCrFeNiV HEAs exhibited the highest resistance in 1 M NaCl and 0.5 M H2SO4 corrosive environments, respectively.

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