Різання та інструменти в технологічних системах
Постійне посилання на розділhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/62923
Офіційний сайт http://rits.khpi.edu.ua/
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)
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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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Документ Purpose and technological properties of granular media for vibration finishing and grinding processing(Національний технічний університет "Харківський політехнічний інститут", 2023) Mitsyk, Аndrii ; Fedorovich, Vladimir; Ostroverkh, YevgeniyThe purpose and characteristics of granular working media used in vibration processing operations are given. It is indicated that the purpose of granular media is their contact interaction with the processed part surface under conditions of various energy parameters. This interaction is accompanied by elastic-plastic deformation, micro-cutting, adhesion and mechanic-chemical processes. Indicators of technological and operational properties for various types of granular media are given, including the intensity of material removal from the processed surface, cutting ability, wear resistance and achieved surface roughness. The physical and technological parameters of granular media have been established, including deformability, hardness during finishing and hardening operations and surface roughness of the media granules. The influence of the parameters of processing media granules on the productivity of vibration treatment has been determined. It is shown that such parameters are the binding of the granules material, its wear resistance, grain material, granulation and the shape of individual granules. It is noted that the choice of granule sizes depends on two main factors such as: the necessity to obtain a given roughness and high productivity of vibration operations. It was revealed that to ensure high surface cleanliness, the use of small granules of the medium is required, but to obtain high productivity, the use of large granules is required. Approximate dependencies have been determined that relate the size and weight of granules of the processing medium and the processed parts. It is indicated that the best results in achieving high quality of the processed surface and sufficient productivity are provided by granular media with a shape close to a sphere. It is noted that granules in the form of cones, pyramids, prisms and other forms are used for the successful processing of hard-to-reach places in the form of small holes, straight and sharp angles in the interface of the surface of parts, niches or pockets. Such granules are specially manufactured from a mixture of grinding powders of various grain sizes and an inorganic binder based on clays. The features of the physical and technological parameters of processing media are given.Документ Regularities of vibration finishing and grinding processing and directions of improvement of its intensity and quality(Національний технічний університет "Харківський політехнічний інститут", 2023) Mitsyk, Аndrii; Fedorovich, VladimirThe data on the labor intensity of manufacturing engineering products and the share of finishing and grinding operations in the total labor costs of their manufacture are presented. The list and the degree of mastering the technological operations of finishing and grinding processing, performed in the conditions of machine-building industries during the last years are given. The grounds are given for highlighting the method of vibration processing as the most promising for ensuring complete mechanization of the process of finishing and cleaning, as well as achieving high technological characteristics of the surface roughness of parts. An assessment was made of the influence of modes, the trajectory of the movement of the reservoir and the grain size of the granules of the abrasive medium on metal removal. It is indicated that the intensity and quality of vibration treatment is estimated quantitatively by the weight removal of metal and qualitatively by the roughness of the processed surface. It is indicated that the determining factor in this case is the speed of the oscillating movement of granules and parts, the difference of which represents the speed of vibration processing, depending on the speed of the oscillating movement of the medium. It is noted that in order to increase the productivity of the process, it is necessary to increase the speed of the medium by increasing the frequency and amplitude of the reservoir oscillations. The layer-by-layer transmission of a force impulse from the bottom of the reservoir to the bulk medium is considered. The physical meaning of increasing productivity by increasing the amplitude of the reservoir oscillations is indicated. The conditions for obtaining metal removal are indicated, which provide increased efforts for the interaction of granules with parts at high micro-cutting speeds. Experimental studies are described to determine the influence of the amplitude and frequency of oscillations on the results of vibration finishing and grinding. Graphic dependences of metal removal were obtained for various ratios of the sample weight to the weight of the medium granule. The dependence of metal removal on the ellipticity coefficient and the amplitude of the reservoir oscillations was obtained in a similar way. It is noted that the vertical component of the amplitude during in-plane oscillations of the reservoir is the determining factor of the complex influence of the parameters of the ellipse coefficient of the trajectory of the reservoir and its amplitude of oscillations. It has been established that when using a coarse-grained abrasive, the penetration of grains into the metal of the part occurs to a greater depth and larger metal chips are removed with a large metal removal. With a small grain size of the abrasive, small chips are removed with a small metal removal and a decrease in the height of micro-roughness.Документ The nature of the formation of surface micro-roughness in vibration finishing and grinding processing(Національний технічний університет "Харківський політехнічний інститут", 2022) Mitsyk, A.; Fedorovich, V.The main aspects related to the nature of the formation of surface micro-roughness during vibration finishing and grinding processing are given. It is indicated that the material removal from the surface of the part occurs as a result of the combined action of micro-cutting processes, chipping of metal particles during repeated deformation of the processed surface areas, their fatigue and destruction, the formation, destruction and removal of secondary structures, and adhesion phenomena. It is noted that the real surface after vibration treatment is a set of roughnesses of a certain size, shape and direction. It is defined that the micro-roughness of the surface of the part during vibration finishing and grinding is formed in the form of traces from numerous impacts of abrasive granules on the surface of the part. The largest value of the granule penetration into the processed surface is determined, that makes it possible to characterize the trace from plastic compression in the zone of collision between the granule and the part. The technique and study of the mechanism of formation of surface microroughness is considered. An expression is determined for the normal component of the impact force, which characterizes the main effect on the mechanism of micro-roughness formation. The value of penetration of the granule into the metal of the part is determined. The study showed that the surface micro-roughness during vibration treatment is formed by impacts of granules on the part at different meeting angles. The traces from action of straight and oblique impacts are established. The average height of micro-roughness is calculated. According to the hodographs, the normal velocities of abrasive granules and parts are determined. The average value of the angle of impact of the granules with the part at any point of the trajectory of their movement is also determined. It was revealed that the velocities of granules and parts change in magnitude and direction during one period of the reservoir oscillation, reaching their limiting values, which are proportional to the reservoir movement velocities. The degree of proportionality is expressed by the similarity coefficient for the granule and the part. The average similarity coefficient was also determined by the points of the hodograph. The average values of the movement velocities of the granule and the part in the reservoir are obtained. The minimum and maximum value of the granule penetration into the surface of the part is established. The formulas for the limiting values of the granule penetration depth are given, taking into account the coefficient of ellipticity. The results of calculations for determining the height of micro-roughness of the processed part surface are presented. A formula is obtained for determining the surface micro-roughness during vibration finishing and grinding processing.