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Документ Surface modification of synthetic grinding powders diamond with heat-resistant oxides and chlorides liquid phase application method(Національний технічний університет "Харківський політехнічний інститут", 2022) Lavrinenko, V.; Poltoratskiy, V.; Bochechka, O.; Solod, V.; Ostroverkh, Ye.; Fedorovich, V.The restrictions to the selection of oxides, which may be interesting in the modification of forging heat-resistant oxides of the surface of diamond grinding powders, are defined. It is shown that the first group of the most efficient applied for modifying the surface of the diamond grinding powders includes the following oxides – B₂O₃, TiO₂, SiO₂ and Al₂O₃. The second group, less effective – ZnO, BaO and CaO. To achieve an additional positive effect from the modification it is possible to consider a double modification of surface of diamond grains with a mixture of oxides of the first group and chloride (СаСl₂, NaCl). The process of grain surface modification of synthetic diamond grinding powders by heat-resistant oxides and chlorides of metals and non-metals by liquid phase application has been studied. The structural characteristics of the external structure have been studied and the quantitative elemental composition of the surface of modified powders has been determined. It is established that to achieve a guaranteed increase in wear resistance of diamond wheels when grinding hard alloys at least 2 times it is recommended to modify the surface of diamond grains with a combination of oxides: B₂O₃ grain surface modification (50 % grain) and Al₂O₃ grain surface modification (50 %).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.Документ Theoretical justification of rational conditions for produsing diamond wheels on ceramic bonds(Національний технічний університет "Харківський політехнічний інститут", 2022) Fedorovich, Vladimir; Ostroverkh, Y.; Pyzhov, Ivan; Lavrinenko, V.The article describes the results of theoretical studies using 3D finite element modeling, which made it possible to determine the rational characteristics of diamond wheels on ceramic bonds. The influence of the parameters of the diamond-bearing layer on the change in its stress-strain state in the sintering zone of the diamond wheel has been studied. The results of finite element and microlevel 3D modeling of the sintering process of a ceramic-matrix diamond-containing composite are analyzed. The influence of the technological parameters of the process and the characteristics of the diamond wheel on the integrity of the grains during sintering was established, on the basis of which practical recommendations were given for the selection of diamond compositions with rational properties.Документ Main technological factors determining the efficiency and quality of the vibration process(Національний технічний університет "Харківський політехнічний інститут", 2022) Mitsyk, A. V.; Fedorovich, V. A.; Grabchenko, A. I.The factors that determine the efficiency and quality of vibration treatment are indicated. Characteristic cases of interaction of abrasive granules with the processed surface are noted. The influence of the hardness of the processed part material and the shape of its surface, as well as the influence of chemically active solutions on the efficiency and quality of vibration processing, is substantiated. The characteristics of abrasive granules and their volume ratio with the processed parts are given. It is indicated that the underestimation of the possibilities of vibration processing technologies is explained by their insufficient studies. It has been established that vibration processing, depending on the characteristics and composition of the processing medium, is a mechanical or mechanochemical removal of the smallest particles of metal or its oxides and plastic deformation of microroughness due to mutual collisions of the medium granules with the processed surface, caused by vibrations of the reservoir in which the processing medium and, the processed parts are placed. It is noted that, according to the classification, vibration treatment refers to mechanical processing methods and, in particular, to the group of mechanical-chemical processing methods or to combined methods when chemically active solutions are introduced into the working medium, It is also noted that vibration treatment refers to dynamic, and for technological purposes – to dimensionless processing methods, according to the type of tool used - to the group of processing methods with a free abrasive. It has beene stablished that the efficiency of vibration processing depends on the oscillation modes of the vibrating machine, the mass of the processed parts and abrasive granules, the hardness of the parts material and the shape of their treated surfaces, the characteristics of the abrasive medium, the volume ratio of the parts and abrasive granules, as well as on the composition of the chemically active solution. The characteristic cases of interaction of abrasive granules with the processed surface are given. The situations of the highest processing productivity for performing the operations of vibration grinding, vibration polishing, washing and descaling have been established. It is noted how the hardness of the processed part and the shape of their surface affects the performance and quality of vibration processing operations. The characteristics of the working medium, which affects the efficiency and quality of vibration treatment, are given, including the influence of grain size and hardness of the material of abrasive granules. The volume ratios of abrasive and processed parts are considered. The types of actions on the vibration treatment processes are given.Документ Methodology for developing an expert system for the grinding of superhard materials(Національний технічний університет "Харківський політехнічний інститут", 2022) Fedorovich, V. A.; Pyzhov, Ivan; Ostroverkh, Y.; Pupan, L. I.; Garachenko, Ya.An expert system of the grinding process has been developed, which makes it possible to predict and optimize the process of defect-free processing of both existing and newly created superhard materials. The expert system consists oftwo interconnected modules - theoretical and experimental. The theoretical module ofthe expert system allows, at a given level of significance, to determine the values of the output indicators and the kinetics of their change in the process of adaptability, depending on the physical and mechanical properties of the interacting materials and processing conditions. The experimental module of the expert system allows you to coordinate and correct the results of theoretical calculations when determining the optimal grinding and operating conditions for processing various grades of superhard materials. When optimizing the sharpening process of a blade tool, processing efficiency, consumption of diamond wheels, cost price and various quality indicators of its cutting elements can be selected as a criterion. The use of the expert system significantly reduces the amount of expensive and laborious researches in determining the optimal processing conditions for various grades of superhard materials (SHM), including newly created ones.Документ Methodology of definition of optimal diamond wheel characteristics at stages of production and operation(Національний технічний університет "Харківський політехнічний інститут", 2022) Fedorovich, V. A.; Pyzhov, I.; Ostroverkh, Y.The problem of increase of effectiveness of manufacturing and application of diamondabrasive tool is still a challenging research subject. Development of computer facilities opens up possibilities for development of three-dimensional (3D) methodology of integrated study of the interconnected processes of manufacturing and exploitation of diamond-abrasive tool and improvement of the single-point tool reliability at the stage of tool sharpening. Creation of the methodology of 3D simulation of processes of diamond-abrasive tool sintering and processes of machining allows to increase essentially validity of the obtained results, to reduce volume of experimental researches for definition of optimum grinding conditions and to develop new technologies, tools and equipment. The developed methodology gives the opportunity to create expert system for assignment of rational characteristics of diamond wheels and grinding modes. The proposed 3D methodology to research processes of diamond-abrasive machining covers all basic stages of life cycle of the tool, including processes of manufacturing and exploitation. Subsystem of computer-generated determination of conditions of manufacturing of defect-free diamond wheels and grinding of superhard materials on the base of 3D simulation of deflected mode of elements of the "SHM crystal grain – metal phase – grain –bond" system at process of diamond wheel sintering and grinding is developed.