Progressive technologies and systems of mechanical engineering

GRINDING OF HARD ALLOY VK15 WITH DIAMOND WHEELS ON A METAL BUNDLE

2025-07-28T13:27:40+00:00

The article presents data on the study of changes in the arithmetic mean deviation of the profile of the treated surface during diamond grinding of the VK15 hard alloy with diamond wheels on the M2-01 bundle, the working surface of which was obtained as a result of electroerosion straightening.

TRIBOTECHNICAL PROPERTIES AND STRUCTURE OF ZINC-ALUMINIUM COATINGS OBTAINED BY CENTRIFUGAL INDUCTION SURFACING

2025-07-28T13:36:45+00:00

The article presents data on the results of studying the structure and tribological properties of a coating made of zinc-aluminum alloy ZnAl30, formed on the inner surface of a steel bushing by the method of centrifugal induction surfacing. The structure of the deposited coating under centrifugal rotation conditions has a composite gradient structure, represented by a matrix Zn-Al alloy reinforced with inclusions of Al13Fe4 and a diffusion zinc layer on the surface of the steel bushing. Tribological tests have shown that the friction coefficient has an extremum of the minimum value by the coating thickness and is 0.005-0.012, which corresponds to the level of antifriction properties. These values are maintained in a wide pressure range (up to 25 MPa) at a sliding speed of 0.2 m/s.

THE CONCEPT OF CREATING CONTACTLESS ROTARY ACTUATORS AND THEIR APPLICATION IN MACHINES FOR VARIOUS PURPOSES

2025-07-28T13:42:28+00:00

The paper presents the developed generalized concept of creating contactless rotary actuators for effective use in machines for various purposes – non-stop dynamic pumps, single crystal cutting machines, saturators, and other machines. The main scientific and technical tasks on the way to create contactless rotary actuators and approaches to their solution are formulated. The results of a study of the technical and technological advantages and design features of contactless drives with annular rotors are presented, their design options and methods of effective use in tank stripping machines, centrifugal vortex and centrifugal pumps, spindle-less single crystal cutting machines are analyzed.

SURFACE ENGINEERING OF METALLIC MATERIALS USING A HIGH POWER DIODE LASER

2025-07-28T13:47:01+00:00

The features of surfacing, modification and alloying operations on the surfaces of steel samples using radiation from a powerful diode laser are investigated. Broadband laser surfacing was carried out using 20X13 stainless steel powder and ZTS-60WCS nickel-based carbide powder. The possibility of melting a similar T-Thermo 660 carbide powder applied in the form of a slip coating with a thickness of ~ 200 μm was tested. B₄C and WC carbide powders were used as alloying materials in these experiments.

INFLUENCE OF STRENGTHENING FIBER ORIENTATION ON THE STRESS STATE DURING TORSION OF CYLINDRICAL SPECIMENS

2025-07-28T13:52:51+00:00

This paper investigates the influence of the spatial orientation of strengthening fibers, formed by surface plastic deformation (SPD), on the stress state of cylindrical specimens under torsion. Numerical simulations were conducted in ANSYS for three fiber orientation angles: 0°, 45°, and 90°. It was found that a 45° inclination provides the most uniform distribution of shear stresses and the highest torsional strength. Fibers aligned along the axis (0°) exhibit lower resistance, while transverse orientation (90°) results in the weakest performance. The findings highlight the importance of selecting an optimal fiber orientation based on the operational conditions of the component.

WEAR-RESISTANT COATINGS FOR OPERATION OF MACHINING TOOLS IN HEAVY-DUTY CONDITIONS OF THE CONSTRUCTION INDUSTRY

2025-07-28T13:56:02+00:00

Increasing the service life of the processing tool in the construction industry is achieved by using various types of coatings. One of the promising areas for achieving a high service life is the use of vacuum coatings. Coatings based on titanium and zirconium compounds are known and widely used. However, three-component coatings based on aluminum-titanium-nitrogen are currently of interest from the point of view of technical application. The purpose of this work was to study the morphology and physical and mechanical properties of vacuum coatings obtained on the basis of altines. To study the characteristics of protective layers based on aluminum-titanium-nitrogen, modern research methods were used: optical and atomic force microscopy, microdurametry, tribological tests. It was found that the formation of three-component coatings based on aluminum, titanium and nitrogen allows the formation of highly hard coatings even at low values of the reaction gas in the vacuum chamber. The morphology of the formed coatings depends on both the potential supplied to the substrate and the pressure of the reaction gases in the vacuum chamber. The friction coefficient of AlTiN-based coatings depends on the magnitude of the vacuum that was created during the formation of the coatings using the plasma-chemical method.

RESEARCH OF THE KINETICS OF WEAR OF THE CUTTING WEDGE AND CONTACT STRESSES ON ITS WORKING SURFACES

2025-07-28T14:00:44+00:00

The article discusses the nature and distribution of contact pressure on the front and rear surfaces of the cutting wedge (CW) given the radius of the rounding of the cutting edge (ρ) which determines the size of CW together with the front and rear corner cutter. The kinetics of the radius ρ cutters from superhard materials in the processing of hardened steels. Determined pair correlations between actual slice thickness a and ρ_st and providing the greatest strength and ρ_d of CW, the corresponding maximum tool life for fine and finishing hard materials, including hardened steels and superalloys. Given the magnitude of normal forces, friction forces and specific loads at run-cutter turning part of a composite 01 hardened steel HV1G. The character of changes in the normal and shear stresses with increasing cutting speed and feed per revolution. Recommendations are given on the optimal assignment of the cut section of fine turning at the value of the rounding radius of cutting edges of cutters of unified designs.

IMPROVING THE EFFICIENCY OF HIGH-RESOURCE REINFORCEMENT TECHNOLOGY

2025-07-28T14:05:22+00:00

The article substantiates the possibilities of increasing the efficiency of combined hardening surface treatment of reusable loaded parts. The analysis of the operational features of the physico-mechanical condition of the blade surfaces in corrosive environments has been performed. Possible combinations of effective technological schemes of surface treatment are proposed to obtain operationally oriented quality indicators of blade structures in relation to alternating loads under extreme operating conditions.

THE EFFECT OF CHANGES IN THE MATERIAL OF CONTACTING PARTS ON CONTACT STRESSES IN MESHING OF TRANSMISSIONS WITH INTERMEDIATE ROLLING BODIES AND FREE CAGE

2025-07-28T14:10:55+00:00

This article discusses transmissions with intermediate rolling bodies and free cage (IRBFC). A diagram of a transmission with IRBFC is presented. The shapes of the rolling elements and the materials from which they can be made are considered. Materials used for the manufacture of parts with a cycloidal profile are studied. The influence of the materials of the rolling elements, cam, and ring gear of a transmission with IRBFC on the contact stresses in its meshing is investigated.

EQUIPMENT FOR APPLICATION OF PLASMA WEAR-RESISTANT COATINGS BASED ON M-CROLL

2025-07-28T14:15:30+00:00

A set of equipment has been developed for the formation of plasma wear-resistant coatings based on M-rolls. The characteristics and parameters of the developed set of equipment for the formation of plasma coatings are presented, as well as the results of its testing. To implement new technological schemes for applying coatings with improved performance characteristics, a whole range of new equipment has been developed, patented and manufactured. The experiments carried out show that the PBG-1 plasma torch and the PPBG-04 powder feeder developed by the authors have at least a 2-3 times higher service life when spraying materials from M-rolls and ceramics compared to serial equipment from the Plasma-Tekhnik company, due to changes in the design of the cathode-anode unit of the plasma torch and the design of the feeding unit of the feeder, facilitating uniform supply of powder into the plasma jet and better penetration. The result is higher quality plasma coatings with improved performance characteristics: adhesion strength increases by 1.3-2 times, material utilization rate by 1.5-1.6 times, microhardness by 1.2-1.4 times, porosity decreases by 2-2.5 times.