Різання та інструменти в технологічних системах

Постійне посилання на розділhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/62923

У збірнику публікуються наукові статті, у яких висвітлюються актуальні питання в області механічної обробки сучасних матеріалів із застосуванням високопродуктивних технологій, нових методів та вимірювальних приладів для контролю якості оброблених поверхонь і високоефективних різальних інструментів. Висвітлюються аспекти оптимізації й математичного моделювання на різних етапах технологічного процесу.

Рік заснування: 1966. Періодичність: 2 рази на рік. ISSN 2078-7405 (Print)

Новини

Збірник «Різання та інструменти в технологічних системах» включено до Переліку наукових фахових видань України з технічних наук до категорії «Б» згідно Наказу МОН України №409 від 17.03.2020 р.

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Roughness investigation of single and double cutting marks on face milled surface
(Національний технічний університет "Харківський політехнічний інститут", 2023) Nagy, Antal; Kundrak, Janos
In machining with defined cutting edge tools, in some rotational tool processes (e.g. face milling) the tool edge may scratch the surface of the workpiece one more time, depending on the cutting conditions, during one revolution of the tool. As a result, the topographies with single or double cutting marks will be different from each other. The deviation, depending on its size, can also affect the functional performance (e.g. friction conditions) of the operating surfaces. In this article, face-milled topographies created with a symmetrical setting and with single or double milling marks are compared according to the magnitude of the roughness and the degree and nature of the inhomogeneity.
Analysis of the effect of varying the cutting ratio on force components and surface roughness in face milling
(Національний технічний університет "Харківський політехнічний інститут", 2023) Felhő, Csaba
Traditional machining processes, such as face milling, still play a very important role in the production of machine parts and are the subject of ongoing research. One important area of research is the investigation of high-feed milling processes. However, due to the increased feed per tooth value fz, it is advisable to reduce the depth of cut (aₚ) in order to maintain the cutting forces at an appropriate level. In this way, the ratio of these two technological parameters, the so-called cutting ratio, changes and we can move into the range of inverse machining, where aₚ / fz < 1. In this paper, the consequences of this change is investigated on the surface roughness and the components of the cutting force, and it is discussed how the optimal cutting ratio can be found.
Experimental investigation of tribology-related surface topography parameters and hardness of 16MnCr5 case hardened steel
(Національний технічний університет "Харківський політехнічний інститут", 2023) Nagy, Nora
Tribological properties are determinant in the functionality of contacting surfaces of machine elements. The wear resistance or load bearing capacity influence the lifetime of these parts. In this study tribology-related surface topography parameters (Ssk, Sbi) and the hardness of hard turned surfaces are analyzed after hardness and topography measurements. Correlation coefficients were calculated for their relationships. It was found that the cutting parameters affect the wear resistance and the hardness in the opposite direction.
Investigation of face milled surface topography on C45 workpiece assuming movement at 30° and 60° to feed direction
(Національний технічний університет "Харківський політехнічний інститут", 2023) Nagy, Antal; Kundrak, Janos
When surfaces with anisotropic texture are moved in different directions related to their assembled counterpart during operation, the friction conditions change, as they are determined by the lay of the topographies. In the article, contributing to the exploration of this characteristic, we analyze the inhomogeneity of the topography on a face milled plane surface with a symmetrical setting in sections at an angle of 30° or 60° to the feed direction. Roughness profiles are recorded at 13 pointslocated equidistantly from each other in each measurement plane, and the degree and distribution of the roughness deviations are determined on the surface.
Analyzing the effect of the tool pass number and the direction of sliding burnishing on surface roughness
(Національний технічний університет "Харківський політехнічний інститут", 2022) Nagy, Antal; Varga, Gyula
Nowadays, the concern of environmental protection is becoming more and more important in production as well. They often contribute to this by reducing or eliminating the amount of coolants and lubricants, or by using alternative machining methods. One of them is burnishing, which makes a positive effect on surface integrity, while reduces the environmental load. In this paper we examined the change in surface roughness achieved by burnishing after turning on a corrosion-resistant steel workpiece, where the number of burnishing passes and burnishing direction were changed. The results showed increased smoothness, bearing capacity and dimensional stability by increasing the number of passes from 1 to 2, however, the 3 times repetition did not show any additional favorable improvement on the surfaces. In case of the forward-backward-forward burnishing directions, further chipping occurred, in other cases the effect of the directions was negligible on the amplitude roughness parameters, but considerable on the parameters characterizing the roughness peak. The greatest improvement was achieved with the backward-forward settings.
The effect of burnishing process on skewness and kurtosis of the scale limited surface
(Національний технічний університет "Харківський політехнічний інститут", 2022) Ferencsik, Viktoria; Varga, Gyula
In this paper roughness examination and analysis on burnished low alloyed aluminium surfaces are reported, highlighting 2 parameters from the vertical deviations of the roughness profile from the mean line. From the input parameters of the burnishing process, the effect of burnishing force, feed rate, speed and number of passes are investigated. Measurements of the surface topography – before and after burnishing – are conducted on an Altisurf 520 3D measuring device. The generated and calculated values of the machined surface roughness are analysed in detail with the drawing of the conclusions as well.
Preliminary analysis of surface topography in tangential turning
(Національний технічний університет "Харківський політехнічний інститут", 2022) Sztankovics, I.; Pásztor, I.
Among the productivity-increasing high feed turning procedures, the tangential turning is studied in this paper. Our main focus was a preliminary analysis of the machined surface topography by the DoE method. To achieve this goal 2 kinds of cutting speed, feed and depth of cut were chosen as factors which are influence the surface topography, resulting in 8 experimental setups. After the cutting experiments 2D profile measurements and shape error measurements were done. In this paper the Ra, Rz parameters of the roughness profile, Wa, Wz parameters of the waviness profile and the straightness error were analysed in more depth. We determined their alteration as a function of the studied parameters and designated our further research directions.
Influence of the geometric characteristics of the discontinuous profile working surfaces of abrasive wheels for precision and temperature when grinding
(Національний технічний університет "Харківський політехнічний інститут", 2021) Yakimov, A.; Bovnegra, L.; Tonkonogyi, V.; Vaysman, V. O.; Strelbitskyi, V.; Sinko, I.
Grinding is the most common finishing method for hardened steel parts. Grinding is accompanied by a large heat release in the cutting area, under the influence of which structural changes appear in the thin surface of the processed parts, tensile stress and even microcracks, which significantly reduce the operational reliability of machines that include these parts. The use of abrasive wheels with an intermittent working surface makes it possible to reduce the temperature in the area of contact of abrasive grains with the material of the workpiece and, as a consequence, stabilize the quality of the surface layer of the workpieces. High-frequency vibrations in the elastic system of the machine, accompanying the work of an intermittent wheel, are a positive factor that reduces the energy consumption of the grinding process. However, under certain conditions of dynamic interaction of the tool with the workpiece, parametric resonance may occur, which worsens the geometric and physical-mechanical parameters of the quality of the surface layer of the processed part. The aim of the work is to realize the possibility of predicting the quality parameters of the surface layer of parts during intermittent grinding by studying the influence of the design features of the macrotopography of the working surface of abrasive wheels and processing modes on the nature of the dynamic interaction of the tool with the workpiece and the heat stress in the cutting area. It was found that the parametric vibrations of the elastic system of the machine tool can be shifted to a more stable area, due to an increase in the number of interruptions of the working surface of the abrasive whee l with a constant ratio of the length of the protrusions and depressions. The increase in the number of breaks on the wheel also contributes to a decrease in temperature in the cutting area. It was found that to maintain the stable operation of the elastic system of the machine, it is necessary to reduce the number of cavities on the grinding wheel with an increase in the cutting speed. However, both of these actions are accompanied by an increase in the heat stress of the grinding process. It has been experimentally established that for ordinary (pendulum) grinding, it is possible to achieve an increase in processing productivity by increasing the speed of the longitudinal movement of the table.
Finish machining of the cutting inserts from cubic borine nitride BL group composite
(Національний технічний університет "Харківський політехнічний інститут", 2021) Chumak, A.; Klimenko, S.; Klimenko, S.; Manokhin, A.; Naydenko, A.; Kopeikina, M.; Burikin, V.; Bondarenko, M.; Burlakov, V.
Finishing methods of machining of superhard composite’s working elements based on cubic boron nitride BL group are considered. The results of the microgeometry formation research of the cutting inserts’ surfaces during machining by free powders of synthetic diamond, grinding wheels and a method of vibro-magnetic-abrasive machining (VMAM) are presented. It is shown that during VMAM the friction between the inserts’ surfaces and the abrasive particles result in microremoval of the material, which reduces the roughness of the cutting inserts’ surfaces. It is established that additional fine grinding with 14/10 mkm synthetic diamond powder provides the absence of microgeometry defects of the cutting inserts’ surfaces left by pre-machining. The result of high-quality rounding of cutting edges and the formation of surfaces of cutting inserts with less roughness is an increase in strength and wear resistance of metal-cutting tools in high-speed machining under conditions of significant loads.
Experimental investigation of surface topography of AL7075-T6 alloy machined by EDM
(Національний технічний університет "Харківський політехнічний інститут", 2021) Balanou, M.; Papazoglou, E. L. ; Markopoulos, Angelos P.; Karmiris-Obratański, P.
Electrical discharge machining is one of the most important non-conventional machining processes for removing material from electrically conductive materials by the use of controlled electric discharges. EDM is a non-contact machining process, therefore, is free from mechanical stresses. This paper investigates the machining Al7075-T6 alloy by EDM using a copper electrode. Al7075-T6 alloy was selected, because of its growing use in a lot of engineering applications. The effect of electrical parameters, peak current and pulse-on time, on the surface integrity, was studied. Area surface roughness parameters (arithmetical mean height, Sa, and maximum height, Sz) were measured on all samples and 3D surface characterization has been carried out with confocal laser scanning microscopy. The experimental results showed that the surface roughness is mainly affected by the pulse-on time.