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1

Investigation into the Contamination of Soil with Multiple Components in the Vicinity of Municipal Solid Waste Landfills

Bereziuk Oleh, Pashechko Mykhaylo, Savulyak Valeriy, Kalda Galyna, Prus Aleksandra

Journal of Ecological Engineering

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2024

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Vol. 25, nr 6

206--213

EN

Here determination of the level dimensions regularity of the multicomponent contamination zones (by heavy metals and petroleum products) of the soils adjacent to the municipal solid waste landfill. The dependences of the mercury, copper and zinc concentrations in the soil on the distance to the landfill of municipal solid waste were determined, similar dependence was specified for petroleum products for a distance of up to 500 m. The research employed the regression analysis technique for investigating single-factor experiments and other paired patterns. The selection of a suitable function was based on commonly utilized options, determined by the criterion of achieving the maximum correlation coefficient value. Regression analyses were conducted by employing linearizing transformations, facilitating the conversion of non-linear regularities into linear forms. Graphical dependences, describing the change in the concentrations of individual soil pollutants with the distance from the municipal solid waste landfill have been built, they enable to demonstrating the satisfactory convergence of theoretical outcomes with empirical observations was achieved. The level regularity of multicomponent soil contamination (with petroleum products and heavy metals) at the distance from the municipal solid waste landfill has been obtained, it’s required for determining the dimentions of the zones of multicomponent soil contamination. Applying the method of iterations, the dimensions of the multicomponent contamination zones (with petroleum products and heavy metals) of the soils, adjacent to the landfill of municipal solid waste have been determined: very heavy pollution–22.93 m, heavy pollution–81.77 m, average pollution–474.9 m from the foot of the landfill.

2

Study of the Influence of Cavitation and Magnetic Field on the Change of Water Properties and its Purification in a Vibrating Machine with Determination of Drive Modes

Hordieiev Anatoly, Kalda Galyna, Pashechko Mykhaylo, Hanzyuk Andriy, Tkachuk Vitaliy, Kostiuk Nazar

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no 3

234--245

EN

The paper presents the results of research into the influence of low-frequency sound and magnetic fields on the change in the properties of water and its purification in a vibrating machine with an eccentric drive, which allows obtaining a constant amplitude of oscillation when the frequency of oscillations of the drive is changed. A method and construction of a vibrating machine for changing the properties of water and cleaning is proposed. Thanks to its reciprocating movement, and in the pulsation chamber and the nozzle, appropriate reactions take place. At certain oscillation frequencies, a cavitation cavity appears in the nozzle and the pulsation chamber, in which the process of splitting water molecules into active radicals takes place. At the same time, during the reciprocating movement of water through a non-magnetic nozzle, which is covered by permanent magnets, an additional effect of a variable magnetic field direction is exerted on water, which strengthens the breaking of hydrogen bonds in water molecules. Visualization of the hydrocavitation process during operation of a vibrating machine with a transparent nozzle was studied. During the experiment, changes in water parameters were studied, i.e. changes in pH, changes in the oxidation-reduction potential of treatment ORP and the total content of mineralization according to the TDS index with treatment time. The total concentration of dissolved salts decreases from 400 to 300 units, which also indicates an improvement in water quality. The rational frequency limits of the vibration drive of the machine are in the range from 18 to 23 Hz with an amplitude of oscillations of 0.002 m, and the ratio of its design parameters is determined: with a piston diameter of 0.1 m, it is recommended to use a diameter of the hole in the piston from 0.006 to 0.008 m.

3

Dynamic Processes of Substructural Rearrangement under Friction of Carbon Steel

Shevelya Valeriy, Pashechko Mykhaylo, Kalda Galyna, Sokolan Yulia

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 3

236--248

EN

The effect of heat treatment (tempering temperature after quenching) of medium carbon steels (steel 45 and steel 50) on tribological indicators at sliding friction without lubrication in connection with the change in strength and rheological elastic properties of steel, controlling the dissipative properties of the frictional contact has been studied. Tribotechnical tests were conducted according to two schemes. A high-temperature tribometer was used for “soft” friction according to the “ball-plane” scheme, which allowed varying the temperature of the friction contact. Influence of load-rate modes was studied in more “hard” conditions on the friction machine under the “finger-disk” scheme. Substructural transformations of steel caused by heat treatment were evaluated by changes in amplitude-dependent internal friction on a torsion pendulum-type machine, which also allowed measuring frictional damping (contact internal friction) in the preliminary displacement mode. The interrelation between hardness, elastic modulus and internal friction of steel and wear resistance, wear capacity, friction coefficient and the level of frictional damping has been established. It is shown that the growth of elastic modulus and increase of steel relaxation resistance after the appropriate heat treatment are conjugated with the development of adhesion and setting, which, as topochemical reactions in the solid phase, are the leading forms of contact stress relaxation under the above conditions. Correlation of tribological indicators of external friction with amplitude-dependent and relaxation (temperature-dependent) internal friction taking into account structural state of steel and friction temperature regime is established. Substructural preconditions, dynamic relaxation mechanisms of hardening and load-temperature friction conditions under which martensitic structures exhibit abnormally high wear resistance and significant growth of frictional damping level are considered. The tribological analogue of the Porteuen - Le Chatelier effect, manifesting in the form of frictional self-oscillations in the range of temperatures of dynamic deformation aging is established. A treatment of the nature of the Kael-Ziebel effect, the temperature-rate and load localization of which in friction is associated with the temperature range of dynamic strain aging with Snook-Kester relaxation superimposed, is proposed.

4

Characteristic Features of Structure and Analysis of Friction Behavior of Electric-Spark Coatings from Powder Wires

Holubets Volodymyr, Pashechko Mykhaylo, Borc Jarosław, Shpuliar Yuriy, Hasiy Oleksandr, Honchar Ivan

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 2

299--306

EN

The structure, phase and chemical composition of electric-spark coatings (ESC) obtained on the Elitron installation from powder electrode wires were investigated using a Neophot-2 optical computer microscope, an EVO-40XVP (Carl Zeiss) scanning electron microscope, DRON-3.0 X-ray diffractometer, EXPERT 02L elemental composition analyzer. The structure of the ESC is an austenitic matrix with boride inclusions (Fe,Cr)B, iron boride Fe2B, chromium borides of iron Cr1.65Fe0.35B0.96. The distribution of Cr, Fe and C in these coatings is uneven and varies in wide range. The micromechanical characteristics of the modified surface layer of steel 45 were analyzed using Ultra Nano Hardness Tester and Nan Scratch Tester. The article provides an analysis of the frictional behavior of the ESC under conditions of dry friction and boundary lubrication according to the finger-disc scheme. Frictional stability of such coatings indicates the expediency of using electric-spark alloying (ESA) technology with powder wires (PW) and powder wires with graphite (PWG) to increase the service life of both machine parts and cutting tools.

5

Investigation of the Effect of Young’s Modulus on the Contact Strength of Metal Polymer Plain Bearings

Chernets Myron, Pashechko Mykhaylo, Kornienko Anatolii, Borc Jarosław, Zakhariia Roman

Advances in Science and Technology. Research Journal

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2022

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Vol. 16, no 2

67--73

EN

Using the author's method of research of hybrid (metal-polymer) plain bearings the calculation of their load carrying capacity (contact pressures) is carried out. Studies have been conducted for metal-polymer bearings with a bushing of two types of polymer composites: epoxy based antifriction composite materials DIAMANT Moglice (DIAMANT Metallplastic GmbH) and DK6 (PT) (fillers - graphite, MoS2, Zr). The elastic constants of composite materials, in particular the Young's modulus, have a noticeable effect on the contact pressures in metal-polymer bearings. The Young's modulus is significantly different in these composite materials. In accordance with this factor, the influence of load, bushing diameter and radial clearance on the maximum contact pressures was studied. Quantitative and qualitative regularities of maximum contact pressures from the accepted factors of influence: Young's modulus, loading, bushing diameter, radial clearance, type of bushing material are established. The obtained results are compared with the results obtained by known conventional calculating methods of contact pressures.

6

The Synthesis of Dwell Mechanisms on the Basis of Straight-Line Linkages with Fivefold Interpolation Nodes

Kharzhevskyi Viacheslav, Pashechko Mykhaylo, Tatsenko Oleksandr, Marchenko Maksym, Nosko Pavlo

Advances in Science and Technology. Research Journal

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2021

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Vol. 15, no 1

18--25

EN

The paper deals with the problem of kinematic synthesis of dwell linkage mechanisms which are based on the four-bar linkage with a coupler point that traces a curve with a straight-line part. It enables to obtain a dwell of the output link of the mechanism, but the main goal is to find such parameters of the mechanisms that hold the required conditions of the designer: necessary dwell time, to satisfy the necessary cyclogram of the machine with taking into account the number of additional parameters. The main problem is to carry out the kinematic synthesis of the basic straight-line linkage that can be done by the kinematic geometry methods. In this paper it was shown that the fivefold interpolation nodes of the coupler curve with the tangent line can be successfully used to satisfy the necessary criteria. As a result of the carried out studies, the regions of existence of such mechanism parameters were determined enabling to carry out an optimization procedure using different criteria.

7

Calculation of Contact Pressures in Cylindrical Metal-Polymer Sliding Guides

Chernets Myron, Pashechko Mykhaylo, Kornienko Anatolii, Ishchenko Anatoly

Advances in Science and Technology. Research Journal

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2021

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Vol. 15, no 3

30--33

EN

Guides (linear plain bearings) of reciprocating motion are widely used in many areas of human activity. However, at present there are no reasonable methods for their calculation, in particular metal-polymer guides. The author's method of contact strength calculation of cylindrical metal-polymer sliding guides is presented in the article. The effect of load, bushing diameter and radial clearance on the maximum contact pressures and their distribution in the guide was studied on the example of epoxy-based polymer composite material Moglice of the German company DIAMANT Metallplastic GmbH, which is used to restore tribotechnical sliding systems elements. Quantitative and qualitative regularities of dependence of contact pressures on the accepted factors of influence are established: at loading increase four times the maximum contact pressures and contact angles will increase twice irrespective of change of sizes of a radial clearance and diameter of a base; increasing the base diameter leads to a directly proportional decrease in maximum contact pressures; doubling the radial clearance leads to a -fold increase in pressure, regardless of changes in the magnitude of the load and the diameter of the base. Regularities of change of contact parameters from the specified factors are given graphically.

8

On the Question of Methodology of Hybrid Sliding Bearings Estimated Load Capacity and Durability Evaluation

Chernets Myron, Pashechko Mykhaylo, Kornienko Anatolii, Chernets Juriy, Fedorchuk Svetlana

Advances in Science and Technology. Research Journal

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2020

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Vol. 14, no 4

177--184

EN

The computational method of hybrid (metal-polymer) sliding bearings according to the load capacity and durability of the bushing made of polyamide filled with glass or carbon dispersed fibers was presented. The initial contact pressures were calculated and the influence of bushing wear on their relative reduction was investigated. The wear resistance of bearings with bushings made of both polymer composites was also evaluated. Regularities of their change from loading, diameter of the bushing and radial clearance were established.

9

Analysis of Linkage Mechanisms with Internal Driving Link

Pashechko Mykhaylo, Pasika Viacheslav, Hembara Nataliya, Kharzhevskyi Viacheslav

Advances in Science and Technology. Research Journal

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2020

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Vol. 14, no 1

191--200

EN

The linkage mechanisms with internal driving link that are used in many different machines are considered in the paper. The mechanism contains hydraulic cylinder that is hinged to the rack, a rocker arm that is pivotally attached to the driving rod and to the rack. The law of motion of a rod in a hydraulic cylinder was synthesized. The positions, angular velocities and accelerations of the hydraulic cylinder and the rocker arm are analytically determined by the methods of engineering mechanics and the theory of mechanisms and machines. Thus, brief analytical dependencies are obtained. It is shown that the angular accelerations of the hydraulic cylinder and the rocker arm are qualitatively similar to the relative acceleration of the rod. The results of the work can be used in the motion research of hydraulically driven excavator buckets, other lifting and loading, road building machines, in the actuating mechanisms of industrial robots.

10

Combined method for surface hardening of Р6M5 steel by deposition of N + Ti and N + Cr diffusion coatings and selective laser post-treatment of substrate

Pashechko Mykhaylo, Kindrachuk Myroslav, Khyzhnyak Viktor, Tisov Oleksandr, Zagrebelniy Volodymyr, Yurchuk Alina

Inżynieria Materiałowa

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2019

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Vol. 40, nr 1

9--13

EN

The main aim of current research is to improve wear resistance of tool steels. Chemical heat treatment is a well-known method to do this. Nitriding is a well known method of improving surface hardness and wear resistance. Due to high hardness, low thickness, these coatings often crack and spall out of the substrate. We supposed that varying hardness and composition of the coating will facilitate wear resistance and will help to avoid coating cracking. In this order we propose to use selective laser treatment of cutting edge by laser beam after chemical heat treatment. This locally changes the structure of steel, thus changing the thickness and hardness of coating. A following chemical heat treatment was done — single- (nitriding with laser pre-treatment) and bilayer (nitriding + metallization with laser post-treatment) coatings. Laser post-treatment provides local hardening of steel substrate, with no influence on diffusion layer chemistry. In a work we considered the structure, phase and chemical composition, microhardness of surface areas of steel P6M5 (substitute of PN SW7M, EN HS6–5–2) after chemical heat treatment: nitriding with further titanizing or chromizing and laser post-treatment. For this we used laser installation LATUS-31, radioelectron microscope REMMA 101A. The content of chemical elements was determined by EDS (heavy elements) and WDS (light elements) methods using REMMA 101A built-in facilities. Dry wear test was performed in sliding conditions using block-on-ring test layout. It is proved that combined coatings have better wear resistance versus coatings formed by common nitriding. Laser treatment of substrate prior to chemical heat treatment has a superior effect on the properties of diffusion coatings, increasing their wear resistance in order of two (compared with untreated coatings) Results of analysis indicate that nitrochromized coating on laser post-treated tool steel P6M5 has the best wear resistance under dry sliding friction.

PL

Nowoczesny materiał do produkcji narzędzi skrawających musi mieć dużą wytrzymałość mechaniczną, odporność na zużycie i efektywny stosunek ceny do jakości. Obecnie większość materiałów ma niewystarczającą odporność na zużycie, co powoduje brak narzędzi do cięcia materiałów. Skuteczną metodą wzmacniania stosunkowo niedrogich materiałów takich jak stal P6M5 i inne (substytut PN SW7M, EN HS6– 5–2) jest stosowanie ochronnych powłok dyfuzyjnych. Jedną z powszechnych metod obróbki cieplno-chemicznej jest azotowanie. Jednak taka obróbka ma szereg wad: długi czas trwania procesu, mała grubość powłoki, której duża twardość prowadzi do znacznego gradientu właściwości mechanicznych między warstwą dyfuzyjną a materiałem osnowy. Aby zredukować czas azotowania, proponujemy wstępną obróbkę laserową materiału podstawowego. Azotowanie z następującym nasyceniem tytanem i chromem pozwala dodatkowo poprawić właściwości skrawające stali P6M5. Jednak nasycenie metalu w temperaturze powyżej 1000°С prowadzi do całkowitego odpuszczania materiału osnowy pod badaną powłoką. Aby temu zapobiec, proponujemy przeprowadzenie obróbki laserowej po obróbce cieplno-chemicznej.

11

Fretting-Wear Mechanism of Textured Surfaces

Pashechko Mykhaylo, Marchuk Volodymyr, Kindrachuk Myroslav, Tisov Oleksandr, Kornienko Anatolii, Dukhota Oleksandr

Advances in Science and Technology. Research Journal

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2019

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Vol. 13, no 3

186--191

EN

The wear mechanism of textured dimpled in conditions of lubricated fretting-wear is established, which, in contrast to others, takes into account possibility of removing deterioration products out of tribo-contact areas into dimples, preventing their action as abrasive material. Selection of optimal structural parameters of selectively dimpled areas allows to reduce duration of tribological couple running-in time. Depending on texture type, friction coefficient was reduced from 0.27 (for untreated furface) to 0.18, and wear loss – from 7.8 ×10–3g to 3.3 ×10–3g.

12

Features of Formation Stress State of Amorphized Detonation Coatings of the Zr-Al-B Systems

Pashechko Mykhaylo, Kharchenko Olena, Shchepetov Vitaliy, Lenik Klaudiusz, Gladkiy Yaroslav

Advances in Science and Technology. Research Journal

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2019

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Vol. 13, no 2

46--50

EN

The results of experimental studies on the dependence of the thickness of amorphous-crystalline Zr-Al-B coatings on the value and level of distribution of type 1residual stresses were presented. It was demonstrated that residual compressive stresses arise in the surface layers of coatings, which in absolute value are not significant for its integrity and quality. It was established that the amorphous-crystalline composition, under the conditions of minimizing residual stresses and the optimal combination of the volume fraction of components, the structure and morphology of their components, has the best surface strength and wear resistance under friction compared to tungsten carbide and iron coatings

13

Gradient composite coatings for working surfaces of braking devices

Pashechko Mykhaylo, Kindrachuk Myroslav, Humeniuk Ihor, Berezhanskyi Taras

Advances in Science and Technology. Research Journal

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2018

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Vol. 12, no 2

1--5

EN

In this paper a study to develop a composite wear-resistant coatings for application to the working surface of linings of brake devices, which is based on a rule of a positive gradient of mechanical properties was carried out. These devices and so coatings work in conditions of rapid rise of temperature. Thermal properties of matrix and inclusions should not differ a lot. Otherwise this will cause internal cracking and deterioration of coating. With this purpose we did the analyses of thermal properties of matrix and carbide particles of coating and concluded thet a material with balanced composition based on thermal properties will have the best wear resistance It was created and tested eutectic composites based on alloy steel 12X18H9T based on thermal characteristics of all components. Wear tests indicated the best wear resistance of coating with composition: steel 12X18H9T (matrix) – 75%; fillers TiB2 – 10%, VC – 15%.