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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 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.Документ Modeling the influence of metal phase in diamond grains on self-sharpening of grinding wheels on ceramic bonds(Національний технічний університет "Харківський політехнічний інститут", 2021) Fedorovich, V. A.; Fedorenko, D.; Pyzhov, Ivan; Ostroverkh, Y.The article presents the results of theoretical studies using finite element modeling, which made it possible to determine the rational characteristics of diamond wheels based on ceramic and polymer bonds. The effect of the parameters of the diamond-bearing layer on the change in its stress-strain state in the process of microcutting of hard alloys and superhard materials has been studied. It is established that the determining factor in the occurrence of critical stresses during grinding is the temperature in the cutting area, the increase of which in the presence of metal phase inclusions in diamond grains with high values of thermal expansion coefficient can lead to destructive stresses in grains and, consequently, their premature destruction. It is advisable to use diamond grains with a minimum content of metal phase and the use in the manufacture of synthetic diamonds solvent metals with a low value of this coefficient, which will significantly increase the use of potentially high resource diamond grains.Документ 3D methodology of research of diamond-abrasive machining process(Національний технічний університет "Харківський політехнічний інститут", 2020) Grabchenko, A. I.; Fedorovich, V. A.; Pyzhov, I.; Ostroverkh, Y.; Kozakova, N.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.Документ Increase of efficiency of diamond grinding superhard of materials(Національний технічний університет "Харківський політехнічний інститут", 2020) Grabchenko, A. I.; Fedorovich, V. A.; Pyzhov, I.; Ostroverkh, Y.The analysis of algorithm of expert system of process of diamond grinding superhard of materials (SHPM) is given. For realization of the offered expert system the ways of grinding with the combined control of parameters of a working surface of diamond circles are developed.The designed ways of superhard polycrystallic material diamond grinding basing on control of a grinding wheel surface with usage of simulation of destruction processes of the system "polycrysta-grain–wheel bond" considered.Документ Theoretical reasoning for efficient use of micro powders in diamond wheels on metallic bonds(Національний технічний університет "Харківський політехнічний інститут", 2020) Grabchenko, A. I.; Fedorovich, V. A.; Pyzhov, I.; Ostroverkh, Y.; Kozakova, N.The article presents theoretical researches of improving the manufacturing process and the subsequent using of grinding wheels from diamond micro powders of diamond on currentcarrying bonds, which allow to reduce the specific consumption of synthetic diamonds in the finishing operations of processing polycrystalline superhard materials It is proposed to use diamond grains with a metal coating in an abrasive tool. 3D analysis of the stress-strain state “diamond grain-coating-bond” system showed ways to reduce the probability of destruction of diamond grains during sintering of the diamond-carrying layer by changing the thickness of the coating, the elastic modulus of its material and other parameters. The calculated low values of the concentration of coated diamond grains provide a significant reduction in their specific consumption in the processing of polycrystalline superhard materials.Документ Specificity of using diamond micropowders in wheels on metallic bonds(Національний технічний університет "Харківський політехнічний інститут", 2019) Grabchenko, A. I.; Pyzhov, I.; Dobroskok, V. L.; Fedorovich, V. A.; Ostroverkh, Y.Some issues related to the possibility of increasing the efficiency of shaping blade tools from polycrystalline superhard materials by diamond grinding are considered. It has been established that one of the ways to increase the efficiency of using diamond micropowder grains in circles is to apply thick metal coatings on them. The use of embossed metal coatings on diamond grains can significantly extend their cutting resource. This is explained on the one hand by a stronger adhesion of the coating material to the diamond surface compared to the components of the binder, and on the other hand, a significant increase in the contact surface of the coated grain with the binder of the circle. It was established that the strength of metal and ceramic ligaments should be consistent with the strength of diamond grains sintered with it, and the concentration and graininess of the latter have a significant impact on the integrity of the grains in the sintered layer.Документ The methodology of sharpening of blade tools made of superhard materials(Національний технічний університет "Харківський політехнічний інститут", 2019) Fedorovich, V.; Ostroverkh, Y.; Kozakova, N.High durability of the blade tool from superhard materials (SНM), which have unique physical and mechanical properties, creates the prerequisites for its effective use in automated production. However, the widespread use of such tools is constrained by its relatively low reliability during operation. This disadvantage is due to the imperfection of the processes of obtaining SНM: the presence in it residual stresses, internal defects, which appear even after sharpening and thermo-activated finishing. The processes of sharpening of tool blade from superhard materials and cutting with this tool are characterized by high levels of contact pressures and temperatures in the treatment area. Therefore, it seems inappropriate to choose sparing conditions for its sharpening and refinement to ensure the defect of these processes. In connection with this, a new methodological approach is proposed, which makes it possible to determine the cutting conditions and other conditions for sharpening and finishing the SНM blade tool, in which material defects are revealed even at the tool manufacturing stage. To this end, in the software packages COSMOS, ANSYS, NOSTRAN, Third Wave AdvantEdge, thermo-force stress in the cutting edge of the tool simulated under extreme conditions while its operation. This simulations are the initial data for solving the inverse problem – finding conditions (speed, cross feed, normal pressure in the contact) and other diamond grinding modes (physical and mechanical properties of the bond and diamond grains of the wheel, grain size and concentration) according to the well-known stress-strain state cutter from SНM in extreme conditions of its operation. The proposed methodology allows rejecting defective cutters at the stage of their manufacture, thereby increasing the reliability of operation of blade tool from superhard materials.