International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The object of the study was carbon particles obtained by the method of self-propagating high-temperature synthesis. The purpose of the work is the development of compositions and technologies for obtaining competitive composite materials modified with low-dimensional carbon modifiers based on vegetable raw materials.

The most common coatings for metalworking tools include titanium nitride, titanium carbide, titanium carbonitride, zirconium nitride, zirconium carbide, zirconium carbonitride, compounds based on chromium, titanium, aluminum, diamond-like coatings that are formed in vacuum using PVD, CVD, PCVD methods or a combination of the above methods. The current trend in the deposition of vacuum coatings is the production of multifunctional coatings, which can significantly increase operational characteristics compared to the starting materials. To form multifunctional coatings, the creation of “sandwich” structures is used, since each layer performs various functions – forming, antiwear, anticorrosion. Thus, the use of a composite multilayer coating containing layers of titanium nitride, titanium, diamondcontaining compounds with a thickness of one layer from 0.1 to 2 microns makes it possible to increase the wear resistance of a metalworking tool by 1.5-5 times.

The research of the technology of obtaining new copper-ferrochrome composite material has been done. The results of its structure and properties analysis are presented. The material structure consists of the copper base, non-dissolved coarse inclusions of ferrochrome, diffused zones, forming around these inclusions and phases, having formed in the place of completely dissolved inclusions of ferrochrome fine particles. The material has good mechanical properties and a high wear resistance due to the formed solid solutions of the carbides in the copper.

The study of the structure and physicomechanical characteristics of carbon nanostructures, lubricants and cooling liquids was carried out by methods of scanning electron microscopy, atomic force microscopy, IR spectroscopy, physicomechanical and physicochemical analysis. Tribotechnical tests were carried out on a friction machine operating according to the “sphere – plane” scheme.The possibility of modifying various liquid media with nanosized carbon particles of various composition, structure, production technology, including those obtained by the method of self-propagating high-temperature synthesis, has been studied. The studies carried out made it possible to establish general trends in the implementation of the synergistic effect in liquid matrices differing in structure, polarity of macromolecules, and molecular weight.

Methodological approaches to the implementation of the nanostate phenomenon in the formation of the optimal structure of composite materials and metal-polymer systems at different levels of organization have been developed. The concept of energy and technological compliance of functional composite materials and systems components, which determines the optimal parameters of stressstrain, adhesion and tribological properties under technological influences on the components in the process of obtaining composite and its processing, is proposed.

Influence of small Sc, Ag, Zr, Ti, Mn addition on the stabilization of the structural state, the formation mechanisms and kinetics of the phase growth during the aging, and also technological casting properties in the industrial Al-Mg alloys were investigated. It has been established: maximum strengthening in these alloys is reached after the nature aging due to the precipitation of ordered Al3Mg phase that is isomorphic to the matrix. However, under prolonged nature aging the stable Al3Mg2 phase is precipitated in the matrix and on the grain boundary. It is accompanied by fall of the plasticity and decreasing the volume fraction of the strengthening Al3Mg phase. It is succeeded completely to prevent the formation of the stable phase under prolonged nature aging in the alloys quenched in the oi l and additional alloyed by Sc or Ag. Also Ag affects the cracking under the crystallization of alloys favorably. Using the complex of the Zr, Ti, Mn and Sc alloying elements increases the strength properties of the alloy at the quenched state slightly, but accelerates the formation of the stable phase during the nature aging.

The article deals with current situation of design of production lines in modern factories and describes possibilities of realization new type of industry lines. The main research deals with proposal of modular production system established from intelligent manufacturing cells. Main positive features of suggested structure are possibility of rapid reconfigurability of the production line, easy maintenance and possibility of simple and fast design of new production lines, thanks to modularity. To achieve these features in the Industry 4.0 ecosystem is necessary to use of modern communication methods and technologies, such as wireless industrial communication and IoT together with cooperative robots. Moreover, the entire system has to be designed as hierarchical, demand synchronized, flexible and is using standardized construct components.

A series of piston hypereutectic silumin based on Al – (15÷20) % Si, alloyed with copper, magnesium, nickel, chromium is investigated. The mechanical characteristics of ingots from experimental alloys were determined: temporary tensile strength, hardness, relative elongation depending on the composition of the alloys, and temperature coefficient of linear expansion (TCLE). It is shown that the tensile strength of forged blanks is 1.5-2.4 times higher than ingots of hypereutectic silumins. The resulting structure of forgings ensures their high plasticity (relative elongation δ = 5.7÷7.5%; relative narrowing Ψ = 10.3÷14.2%). The optimal mode of heat treatment of deformed silumin is determined: quenching from step heating and aging, which allows increasing the strength of forgings up to 370-470 MPa. Moreover, the plasticity indicators remain at a high level, and the average thermal expansion coefficient of the alloys is (18.0 ÷ 19.2) · 10-6 K-1 in the range of 50 ÷ 200 ° C.

The paper considers the impact of functionalized nanosized carbon particles on the physicomechanical characteristics of composite materials based on polyamides. The concentration of the modifier varied both in the field of “doping” concentrations and in the field of concentrations used in the industrial production of nanocomposite materials based on polymer matrices. It was found that the use of cryogenic treatment of the initial polyamide leads to an increase in physical and mechanical characteristics. The introduction of nanodispersed particles in the field of “doping” concentrations increases the strength and hardness of the developed compositions based on a polyamide matrix.

The reversion in magnesium binary alloys with rare-earth metals (Nd, Sm, Y, Gd, Tb, Dy, Ho) at a temperature of 300ºC has been studied. The phenomenon of the reverse dissolution of rare-earth metals in solid magnesium has been established to begin in all alloys under study already after short-term annealing at 300°C for 15 min. As the annealing time at 300°C further increases, the reverse dissolution of rare-earth metals in solid magnesium first continues and then the magnesium solid solution becomes again depleted of rareearth metals because of their precipitation. The degree of reversion has been found to generally increase with an increase in the atomic
number of the yttrium-group rare-earth metal in accordance with its position in the lanthanum row: Gd, Tb, Dy, and Ho. The degree of reversion in the alloys with cerium-group metals (Nd, Sm) with atomic numbers below those of Gd, Tb, Dy, and Ho is substantially smaller than that is in the alloys with yttrium-group metals.

The results of the effect of preliminary thermal-cyclic deformation on the microstructure of hot-rolled low-carbon steel Ст3пс are presented. It is shown that the regime of thermal-cyclic rolling leads to a decrease in the average grain size of ferrite from 8 to 6 microns in comparison with the structure of steel after industrial production. There is a decrease in the size of pearlite colonies and their volume fraction in the structure of steel after using thermal-cyclic deformation. The results of the effect of heat treatment: normalization and tempering on the electrical resistivity of the hot-rolled carbon steel sheet Ст3пс produced using thermal-cyclic mode of deformation processing (DTCT). DTCT preliminary thermal-cyclic was rolled (5 cycles at a reduction of 10-15 % in each cycle and cooled to a temperature below the Ar1). And normalizing annealing was carried out in the range from 100 to 900 °C increments to 100 °C for 1 hour. The possibility to reduce the magnitude of the specific electrical resistance of the hot-rolled steel manufactured using DTCT mode through the use of subsequent normalizing at 700 °C on average 10 %, and by annealing – no more than 5 %. A further increase in the time of normalization at 700 °C to 3, 5 and 10 hours has no significant effect on the value of the electrical resistance of the steel subjected DTCT. However, the downward trend in resistivity is maintained. Overall reduction of electrical resistivity of the hot-rolled steel Ст3пс by using
mode DTCT and subsequent normalizing at 700 °C for 1 hour is more than 12 %.

Using an originally developed laboratory controlled air cooling automatic device regimes of controlled fasted normalization of low and middle carbon steel were studied. Significant improving of the steel structure was shown. The proposed technologies of controlled air cooling could be useful for small metal products of middle carbon steels heat treatment as an advanced normalization process.