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Документ Reducing the energy capacity of diamond spark grinding by application of solid lubricant(Editura "Academica Brâncuşi", 2020) Gutsalenko, Yu. G.; Iancu, Cătălin; Rudnev, Alexander ; Strelchuk, R. M.Diamond spark grinding is known for lower thermo-mechanical stress of mass micro-cutting in the processing zone compared to conventional diamond grinding. This made it possible to propose the organization of the process using the minimum lubrication methodology as an alternative to the conventional jet watering of the treatment zone with water-based lubricating and cooling technological agents. On the example of using an equilibrium mixture of stearin and sebacic acid, it is shown that the introduction of a solid lubricant reduces the ene rgy intensity of diamond spark grinding in comparison with its support with conventional jet watering. The main explanation for this is to reduce the tribological and thermo-mechanical load on the cutting grains and the working surface of the grinding wheel as a whole due to the application of solid lubricant directly to the working contact surface of the tool. The results of the performed experiments make it possible to predict thermo-physically and physic-mechanically intensified schemes of defect-free diamond spark grinding of hard alloys and other difficult-to-machine materials, in particular, with increased contact pressures or cutting speeds. The development of oriented material science practical recommendations in this direction involves additional research with control of the physical quality of the treated surface.Документ Application of minimum lubrication methodology for diamond spark grinding(Editura "Academica Brâncuşi", Târgu Jiu, 2020) Gutsalenko, Yury; Iancu, Cătălin; Rudnev, Alexander; Strelchuk, R. M.The electric discharge bases of the technological advantages of diamond spark grinding make it possible to consider this processing method among the environmentally promising in nature. A decrease in the thermo-mechanical tension of mass micro-cutting in the zone of diamond spark grinding, which is ensured by the development of its working relief, supported by the action of electric discharges on the bond of the wheel, also makes it possible to consider approaches to organizing this process using the minimum lubrication methodology. The paper presents and summarizes the experimental results of using a number of solid lubricants, gives practical recommendations and defines the tasks of further research. Work in this direction is focused on reducing the use of water in servicing industrial needs, which is an urgent global environmental challenge to the development of civilization and meets the modern technocratic strategies of the European Union (Industry 4.0), Japan (Society 5.0), China (Made in China 2025) and other leading world economies.Документ Investigation of the removal of the diamond layer of a wheel during ed grinding with changing polarity of electrodes(Editura "Academica Brâncuşi", Târgu Jiu, 2020) Strelchuk, R. M.The article investigates the features of the formation of holes on the surface of a bond of grinding wheels. The impact of electrical discharges on the bonds of groups 2 and 4 causes the formation of altered surface layers with increased mechanical properties, which contribute to more durable retention of grains. The main factors affecting the thickness of the modified layer are the pulse energy, wheel rotation speed, and the amount of fluid supplied to the cutting zone. In bonds of group 1, due to the low value of the Palatnik's criterion, the electroerosive effect shapes a very developed relief, the protrusions of which have more grains. In bonds of group 3, including nonconductive components, discharges with the energy of more than 0.05J cause the appearance of cracks. Therefore, an instrument with bonds of groups 1 and 3 should be operated with pulse energy not exceeding 0.05J.Документ Analysis of residual stresses and durability of the cutting inserts after diamond-spark grinding(Editura "Academica Brâncuşi", Târgu Jiu, 2020) Sizyi, Yury; Strelchuk, R. M.; Jha, Shailendra Kumar; Rudnev, Alexander; Gutsalenko, YuryThe article presents an analysis of residual stresses and resistance of cutting inserts after the diamond-spark grinding. In the entire investigated range of traverses (0.01...0.07mm/double stroke) and wheel speed (18...32m/s), the total residual oriented stresses in both phases are compressive and they have an extreme character with a point of extremum (minimum) in the center of the interval (Sпоп = 0.04mm/double stroke; Vкр = 25m/s). In the carbide phase, the main share in the formation of the total stress state of the surface layer of the STIM-3B (СТИМ-3Б) hard alloy is made by macrostresses. The mechanism of their formation is thermal at small and large values of the traverse and wheel speed, and power one—at medium values. The importance of interfacial microstresses in this phase is minor. In the binding phase of nickel, the interfacial component contributes significantly to the formation of the general stress state, due to the force factor at average values of the grinding mode mechanical parameters and thermal parameters in the rest of the range. The highest wear resistance of tools made of STIM-3B (СТИМ-3Б) alloy corresponds to the highest value of compressive interfacial microstresses in the plastic phase (Ni).Документ Research of the cutting mechanism at electrical discharge grinding(Національний технічний університет "Харківський політехнічний інститут", 2021) Strelchuk, R. M.; Shelkovyi, O.The paper presents the results of a study of the cutting mechanism during electrical discharge grinding of hard alloys. The cutting mechanism during electrical discharge grinding was studied using mathematical modeling. By means of geometric modeling, a method of grinding cup wear was developed. The functional dependence of the diamonds use factor in the Kw wheel on the technological parameters of processing, wear and tool characteristics were determined. Analysis of the results of the study shows that an increase in efficiency at electrical discharge grinding can be achieved by reducing the wear of S, and by corresponding variation in the concentration of diamonds and technological modes of processing.Документ Surface roughness modeling during electric discharge grinding with variable polarity of electrodes(Національний технічний університет "Харківський політехнічний інститут", 2021) Strelchuk, R. M.The article presents the probabilistic-statistical modeling of surface roughness in the process of electric discharge grinding with the variable polarity of electrodes. The correlation between electric modes of machining and indicators of the quality of the machined surface was established. A probabilistic-statistical model of part surface roughness formed during grinding is obtained, which establishes the correlation between high-altitude surface parameters and electrical machining modes. The developed model makes it possible to calculate the height parameters of the part roughness depending on the electrical modes of grinding. The height of microroughness is determined by the same machining conditions as the depth of erosion pits. It is possible to obtain low roughness if electrical machining modes are reduced.Документ Methodical instructions for laboratory classes in the discipline "Informatics"(2021) Strelchuk, R. M.This is the lab course, wherein you will have the hands on experience. You have studied the support course material (MCS-011 Problem solving and programming). In this part, C programming under DOS, UNIX and WINDOWS environments are provided illustratively. A list of programming problems is also provided at the end of each session. Please go through the general guidelines and the program documentation guidelines carefully.Документ Methodical instructions for laboratory classes in the discipline "Interchangeability, standardization and technical measurements"(2020) Strelchuk, R. M.Metrology is a science of measurement. Metrology may be divided depending upon the quantity under consideration into: metrology of length, metrology of time etc. Depending upon the field of application it is divided into industrial metrology, medical metrology etc. Engineering metrology is restricted to the measurement of length, angles and other – quantities which are expressed in linear or angular terms. For every kind of quantity measured, there must be a unit to measure it. This will enable – the quantity to be measured in number of that unit. Further, in order that this unit is followed by all; there must be a universal standard and the various units for various parameters of importance must be standardized. It is also necessary to see whether the result is given with sufficient correctness and – accuracy for a particular need or not. This will depend on the method of measurement, measuring devices used etc.Документ EDM gap modeling at electrical discharge grinding with change of electric polarity(Національний технічний університет "Харківський політехнічний інститут", 2020) Strelchuk, R. M.; Shelkovyi, O.The paper presents an experimental study and modeling in the Simulink graphical environment of the EDM gap at electrical discharge grinding (ED grinding) with change of electric polarit of difficult-to-machine materials. Based on the experimentally obtained oscillograms of currents and voltages in the cutting zone, an EDM gap model has been developed, which implements the nonlinear dependence of the active resistance of the electroerosion gap on its value, which makes it possible to take into account the effect of the interelectrode environment on the parameters of electric discharge pulses. Comparison of the calculated oscillograms obtained in the Simulink model with the experimental ones has shown that during ED grinding, the developed EDM gap model adequately reflects the real electrical processes occurring in the electroerosion gap.