Parameters Of Technological Process Research Articles

The influence of cutting mode elements on the technological parameters of the process of milling blanks of titanium alloy thin-walled parts

The purpose of a rational mechanical processing mode remains an urgent task of pre-production engineering. Known recommendations and methods for selecting this mode are focused on the processing of solid blanks and do not take into account the fact that when processing thin-walled blanks, the temperatures in the processing zone and the surface layer of the blank differ. The study is aimed at identifying patterns in changing the parameters of the milling process of thin-walled blanks depending on the mode elements, as well as developing recommendations for selecting this mode. The authors performed numerical simulation of technological parameters of the milling process of solid and thin-walled blanks made of titanium alloy under various modes. The cutting speed, cutting depth and feed per cutter tooth were varied. The cutting force, power and densities of heat sources and the temperature in the surface layer of the blank, in the contact zones of the cutter tooth with the blank and the chips with the front surface of the tooth were calculated. It has been found that when milling thin-walled blanks, the temperature field differs significantly from that formed when processing solid blanks due to low heat removal from the unprocessed surface. Increasing the feed per tooth by 45% leads to an insignificant decrease in temperatures in the cutting zone (by 5...12%). Increasing the cutting speed by 25%, on the contrary, leads to an increase in temperatures by 5...10%. Increasing the cutting depth leads to an increase in the temperature in the chip-tooth contact zone by 1.5times and to an increase in the temperature in the tooth-blank contact zone.

Аналіз процесу ущільнення порошків вольфраму плакованих міддю

The paper analyzes the pressing process of a composite powder of the tungsten-copper system using the basic mathematical equations describing the deformation processes of a porous body as a function of density and pressing pressure. Several theoretical dependences describing different pressing mechanisms are considered, taking into account modern approaches, namely the discrete-contact model and the continuum model of a continuous medium. The most well-known equations, including those of Balshin M.Y., Zhdanovich G.M., and Shtern M.B., are analyzed. It is established that most of them have limited applicability, remaining valid for individual stages of the pressing process and significantly depend on the mechanical properties of the material that determine the predominance of elastic or plastic deformation. At the same time, most equations are focused on single-component powders, which does not correspond to the practice of powdered parts production processes. To test the theoretical dependencies, copper-clad tungsten powder was obtained by chemical vapor deposition from solution. The technological parameters of the cladding process (composition, solution concentration, and deposition time) that determine the quality of the resulting coatings were determined. The morphology of the particles of clad powders and the structure of tungsten-copper pressings were investigated. It is shown that tungsten powder forms a relatively dense framework with a copper layer, respectively, the structure of composite powder pressings is as close as possible to a continuous continuum and is correctly described by an equation based on the theory of continuity of the medium, It has been established that the compaction character of copper-clad tungsten powder differs from that of single-component tungsten powder, which is due to the fact that plastic deformation mechanisms prevail for tungsten-copper composite powders.

Study of the features of concentration inhomogeneities during the on ground-based processing of the space experiment of the Ge(Ga) crystals growth

The article presents the results of the preparation and ground testing of the space experiment for growing Ge (Ga) crystals, planned on board the multifunctional laboratory module as part of the ISS RS. Under the conditions simulating microgravity, the features of the formation of concentration inhomogeneity in the form of growth bands when growing crystals under various thermal conditions (in the presence or absence of a free melt surface (Marangoni convection)), as well as when changing technological parameters (variations in growth rate) were investigated. Based on the obtained results of metallographic and electrophysical studies, conclusions were made about the peculiarities of the influence of the technological parameters of the crystallization process on the structural perfection of the grown crystals under microgravity conditions

Modeling the influence of technological parameters of the magnetron sputtering process using the Caroline D12C system on the proportion of nanocrystallites in the structure of thin silicon films

Modeling the influence of technological parameters of the magnetron sputtering process using the Caroline D12C system on the proportion of nanocrystallites in the structure of thin silicon films

Enhancing the machining productivity in PMEDM for titanium alloy with low-frequency vibrations associated with the workpiece

Abstract The incorporation of frequency vibration into the powder mixed electric discharge machining (PMEDM) process has the potential to significantly enhance the productivity and quality of the machining process, as well as to provide a great deal of opportunities in this sector. An analysis and evaluation of the machining productivity (material removal rate [MRR]) in PMEDM with low-frequency vibration was carried out in this work by considering SKD61 as a workpiece. The oil dielectric solution mixed with titanium powder was used as a dielectric medium with red copper (Cu) as the electrode. At this point in time, the process technology parameters that have been chosen for inquiry are as follows: current (I), pulse on time (T on), powder concentration (C p), P, F, and A. The Taguchi technique (L25) was used to create the experimental matrix. With the use of analysis of variance, it was able to examine the impact that the factors had on MRR, and the analysis was utilized to ascertain the highest possible value of MRR. I was the parameter that has the most significant effect, according to the findings, whereas T on was the parameter that has the least significant effect. The maximum value of the MRRmax is equal to 31.29 mm3/min.

INFLUENCE OF GAS ENVIRONMENT OF SPRAYING ON THE PROPERTIES OF GAS-THERMAL METALLIZED COATINGS

This article is devoted to the study of the influence of the technological parameters of spraying, in particular the gaseous medium, on the physical and mechanical properties and corrosion resistance of gas-thermal metallization coatings. To protect the housings of submersible electric motors (PAD) in oil and gas wells, the method of electric arc metallization (EDM) has become widespread, due to the high level of physical and mechanical properties of the resulting gas-thermal metallization coating, high productivity and cost-effectiveness of the process, as well as the mobility of equipment. Despite the effectiveness of this method of protection, it does not exclude the occurrence of corrosion processes in the metal of the PAD body. In this regard, research aimed at increasing the operational life of the metallization coating is relevant and promising.The article considers the theoretical aspects of the influence of the technological parameters of the spraying process on the properties of the metallization coating. The effect of the sputtering gas medium on the physical and mechanical properties and corrosion resistance of metallization coatings has been experimentally investigated. Comparative tests and studies of gas-thermal metallization chromium-nickel coatings applied by the EDM method in an air environment and in an argon environment have been carried out. The main trends and features of the formation of metallization chromium-nickel coatings applied by the EDM method and the effect of the application mode, in particular the technological gas spraying medium on the microstructure studied on metallographic grinds using a scanning electron microscope with an attachment for energy dispersion analysis; microhardness determined by the Vickers method are determined; The wear resistance is determined by abrasive wear during friction against non-rigidly fixed abrasive particles and the corrosion resistance of the resulting coatings, determined by autoclave tests during exposure in a simulated environment containing corrosive components.The study of the influence of certain technological parameters of spraying of gas-thermal metallization coatings, including the gas medium, on the properties of the coatings obtained is a fairly promising task aimed at increasing the operational life of the metallization coating, which in the future will reduce the cases of premature failure of oilfield equipment.

Patterns of Changes in the Mechanical and Filtration Properties of Semi-Rock Soils Modified by Jet Cementation

When installing underground structures in soil layers with high groundwater filtration rates, special requirements are imposed on the material of anti-filtration curtains. The conditions of application of jet cementation technology for modification of watered fractured rocky soils of low strength in order to form a composite material with the required mechanical and filtration characteristics are considered.The technological parameters of the cementation process have been experimentally and theoretically determined to ensure the necessary radius of propagation of the bonding mixture, and methods of laboratory and field control of the modified zone have been developed. The maximum permissible values of the controlled parameters have been determined.

Optimization of process parameters in laser cladding multi channel forming using MVBM-NSGA-II method

ABSTRACT Laser cladding multi-channel forming is a complex, nonlinear process characterized by multi-parameter coupling. To determine the technology parameters, an optimization method of multivariate black-box prediction model (MVBM) matching non-dominated sequential genetic algorithm (NSGA-II) was constructed. Multi-channel LC orthogonal experiments were designed. The MVBM was established with process technology parameters as inputs and characteristic parameters reflecting the quality (surface hardness, dilution rate) as responses. The set of optimal solutions for technology parameters by the NSGA-II. The experimental results showed that, under the optimum parameters, the average hardness of the optimized increased by 6.1%, and the dilution rate was reduced by 49.8%. The dilution rate was maintained within the optimal range. The study’s findings can provide theoretical support for optimizing LC multi-objective technology parameters and improving coating quality control.

On determining residual stresses in a viscoelastic coating of arbitrary thickness formed during multilayer application on the inner surface of the straight pipe wall

Abstract The technological problem of forming a coating of arbitrary thickness on the inner surface of the wall of a straight pipe due to the multilayer application of a material having the property of viscoelasticity is considered. It is assumed that during the forming process, the coating experiences the action of inertia forces due to the relatively intense rotation of the coated wall. To determine the residual stresses in the resulting coating, a non-classical model of deformable solid mechanics, based on the concepts of growing continuum is used. With the help of the developed model, boundary value problems are formulated, the solutions of which make it possible to construct the desired residual stress distributions for arbitrary programs for changing the parameters of the implemented technological process.

CUGAS2 КРИСТАЛЛДАРЫ, АЛАРДЫН МҮНӨЗДӨМӨЛӨРҮ ЖАНА ИШТЕТИЛИШИ

In this article, the characteristics of CuGaS2 crystals grown are studied by the gas transport method and the two-temperature synthesis method. The described materials, primarily original ones, as well as the presented materials, allow us to conclude that a wide range of compounds represents an unexplored class of substances, especially in the field of experimental determination of their physic-chemical properties, methods of crystal growth and correlation of material characteristics with technological parameters of the production processes. The growing practical application of semiconductors stimulates research into new materials. In recent years, much attention has been paid to studying the physical properties of multicomponent systems, especially crystals of groups I-II-VI2, which are promising for many technical applications. For a number of crystals of group I-II-VI2, methods for selecting p- and n-type samples have been developed, on the basis of which heterojunctions have been created.

Influence of Processing Parameters on Mechanical Properties and Degree of Crystallization of Polylactide.

This work attempts to assess the influence of process parameters on the change of mechanical properties and the degree of crystallinity of polylactide (PLA). PLA is a biodegradable material that has been widely used in various areas-from packaging, through medicine, to 3D printing, where it is used to produce prototypes. The method of processing is important, because the technological process and its parameters have a significant impact on the quality of the finished product. Their appropriate selection depends on quality and mechanical properties. The process parameters have an impact on the structure of PLA, specifically on the share of the crystalline phase, which is also important from the point of view of the functional properties of the finished product. This work assessed the impact of the technological parameters of the injection process on the final properties of the obtained samples. The obtained results of static tensile strength, hardness and differential scanning calorimetry (DSC) analysis confirm that changing these parameters affects the material properties.

Modifi ed Fuzzy Controller with Optimization of Mode Parameters of Technological Process

Modifi ed Fuzzy Controller with Optimization of Mode Parameters of Technological Process

DSC of biodegradable plastic composites material

AbstractThe article presents the thermal analysis of new, fully biodegradable thermoplastic composites filled with natural additives. The samples were made of thermoplastic material with the trade name BIOPLAST® GS 1289, and the natural filler was powder from walnut shells and chicken egg shells in various mass proportions. Differential scanning calorimetry (DSC) analysis was used to assess the quality of the new materials obtained. Moreover, it allowed to determine and select technological parameters of processing and explain the occurrence of undesirable phenomena related to the processing of these materials. The thermal properties of the obtained samples were determined using a Mettler-Toledo DSC 3 scanning calorimeter by the ISO 11357 standard. The analysis was carried out using the following method: conditioning the sample for 10 min at − 20 °C and heating from − 20 to 180 °C at a 10 K min−1 speed. Each sample was subjected to three measurements according to the given method, the first and second cycle in a row, and the third cycle was performed after 24 h. The mass melt flow rate (MFR) was also determined. The critical share of filler in the matrix (BIOPLAST® GS 1289) and the influence of natural fillers on signals on the curve were determined, and it was related to the processing properties of the developed materials.

Modeling and investigation of combined processes of casting, rolling, and extrusion to produce electrical wire from alloys Al–Zr system

The results of modeling and research of casting, rolling, and extrusion processes for producing wire from Al–Zr system alloys and determining its physical and mechanical properties have been presented. When implementing combined processes for processing aluminum alloys, the number of operations is significantly reduced, productivity and yield are increased.As a result of the conducted research, the influence of alloy preparation modes and their chemical composition on the physical, mechanical and electrical properties of longish semifinished products from Al–Zr system alloys obtained by combined rolling-extrusion (CRE) and ingotless rolling-extrusion (IRE) methods were investigated.The simulation of the CRE process for one of these alloys of the system was carried out in the DEFORM 3D software package using data on its rheological properties obtained by the hot torsion method. Based on the modeling results, the optimal modes for conducting experimental studies were selected.The features of metal forming were experimentally studied, the temperature-velocity and technological parameters of combined processing were found, as well as the properties of cast billets, including those obtained using an electromagnetic mold (EMM). The results of experimental studies of the CRE and IRE processes suggest that it is possible to obtain longish deformed semifinished products from alloys Al–Zr system with a level of physical, mechanical and electrical properties that meet international standards.At all technological stages, including drawing, the structure of the metal was studied, and data on the physical and mechanical properties of hot-extruded rods and wire in cold-deformed and annealed states was obtained.The heat resistance of wire made from the investigated alloys was studied and it was found that after testing at a temperature of 280 °C and a holding time of 1 h, it satisfies the requirements of the AT3 type standard with a maximum permissible long-term operating temperature of 210 °C.Recommendations are given for industrial implementation; alloys containing 0.15–0.20% zirconium and 0.10–0.15% iron are recommended for the manufacture of AT1 type wire without heat treatment, as well as 0.25–0.30% Zr and 0.2–0.25% Fe for AT3 wire type with heat treatment.

Impact of Stress and Material Porosity on Double Boost DC-DC Converter Technology to Enhance Field-Effect Heterotransistors and Heterodiodes Density

Currently, several critical issues in solid-state electronics, such as improving the performance, reliability and density of integrated circuits elements like diodes, field-effect transistors, and bipolar transistors are being intensively addressed. One effective approach to reduce the dimensions of integrated circuits elements is to manufacture them in thin film heterostructures with an optimal manufacturing regime. In this paper, we explore methods to increase the density of field-effect heterotransistors and heterodiodes in the framework of a double boost DC-DC converter. We consider manufacturing this converter in a heterostructure with a specific configuration, where several required areas of the heterostructure should be doped by diffusion or ion implantation. Subsequently, the dopant and radiation defects should be annealed using an optimized scheme. Based on this approach, we provide recommendations for determining the optimal annealing time to achieve the best compromise between increasing density of integrated circuits elements and minimizing local overheating during their operation. We also propose a method to reduce the mismatch-induced stress in the heterostructure. We present an analytical approach to analyze mass and heat transport in heterostructures during the manufacturing of integrated circuits, accounting for mismatch-induced stress. This approach allows for the consideration of spatial and temporal variations in the parameters of technological processes, as well as their nonlinearity.

Optimization of technological parameters of the methane tri-reforming process based on the phenomenon of conservatively perturbed equilibrium

course under the condition of the phenomenon of conservative perturbed equilibrium (CPE) are considered. It is shown that the onset of the CPE point - an extremum of the over-equilibrium concentration - occurs at a certain point in time. Therefore, one of the tasks of optimal control is to calculate the time of occurrence of this point and determine the effect of temperature and pressure on its position. The modeling of the TRM process is performed for an ideal displacement reactor. The DWSIM software product was used to model the TRM process. The kinetic equations were programmed in the form of scripts. The position of the over-equilibrium concentration point was also investigated depending on the initial composition of the mixture. According to the modeling results, it was concluded that the position of the CPE point for product H₂ is constant, and depends only on pressure and temperature and does not depend on the initial composition of the mixture. This allows us to conclude that the control can ensure that the product yield with the maximum concentration is achieved. The problem of optimizing the initial composition of the mixture for the methane tri-reforming process using CPE is formulated: the objective function and constraints are defined, and the solution method is chosen. The optimization problem is to maximize the target product of methane tri-reforming, H2. The solution to the problem is the composition of the mixture (concentrations of CH4, H2O, CO2). As for the constraints, the pressure and temperature are limited by the physicochemical properties of the process and the design features of the reactor, the elemental balance must be maintained, the key component at the input must have an equilibrium concentration at a given pressure and temperature, and the concentrations of other components must be deviated from their equilibrium values. A software implementation of the optimization problem based on the Optimization Toolbox Matlab was performed. The research results indicate an increase in the efficiency of the process (increase in the output of the target component) and the possibility of implementing optimal solutions in real time, which opens up prospects for implementation in existing control systems and development of decision-making systems.

Modeling the conditions for obtaining nanostructures during ion-plasma processing taking into account the quantum-mechanical properties of electrode material

The subject matter of the article is the thermophysical and mechanical properties of surface layers of structural materials using a quantum-mechanical approach. The aim of the article is to adjust the parameters of the heat conductivity and thermoelasticity problem, considering all possible external and internal thermal effects and the quantum-mechanical description of the material structure, for electrodes in vacuum-arc nanostructuring. The task to be solved is to perform calculations using the developed model for a copper cathode considering the energy spent on the formation of nanoparticles during ion-plasma processing with oxygen ions. The methods used are methods for solving nonlinear problems. The following results were obtained. 1. The nature of the dependencies of the maximum temperature, the expected volume of nanostructures, and the maximum depth of their formation on the energy of oxygen ions with charges z = 1 and z = 2 matches previously known dependencies obtained by the classical model, but under quantum-mechanical consideration, the maximum temperature values increase by 15%, the volume of the nanocluster increases by 50%, and the maximum depth of its occurrence increases by 1.5 times. 2. When selecting the parameters of ion-plasma processing for obtaining nanostructures with ion energies 100...500 eV, the previously proposed model with general thermophysical and mechanical properties of structural materials can be used. 3. For technologies with ion energies in the range of 103...2∙103 eV, the previously proposed model can be used but with quantum-mechanical effects of structural materials considered. 4) For technologies with ion energies above 104 eV, calculations should be performed using both approaches (the classical approach and the approach considering the quantum-mechanical properties of structural materials), and after comparison, the variant whose calculation results are closest to the experimental results should be used. Conclusions. The proposed theoretical model using the thermophysical, mechanical, and quantum-mechanical properties of structural materials can be used to adjust the technological parameters of ion-plasma processing to assess the formation of nanostructures in protective and strengthening coatings.

Use of Syzygium aromaticum L. Fermented Plant Extract to Enhance Antioxidant Potential: Fermentation Kinetics

The concept of our research is related to the use of stems from S. aromaticum L. in the fermentation process in order to obtain new cosmetic raw materials with high antioxidant potential that are safe for human fibroblasts (HDFs) and keratinocytes (HaCaTs). This evaluation involves treating cell lines with different concentrations of fermented extracts to establish a noncytotoxic dose range. The focus was on evaluating antioxidant activity (AA), total polyphenol content (TPC), and lactic acid efficiency (LAe). For this purpose, the most favourable technological parameters of the fermentation process of stems were determined, including the type of microorganisms, initial sugar content, plant raw material content, and fermentation time. In the present study, lactic acid was obtained with maximum efficiency by stem fermentation in the presence of lactic acid bacteria (LAB) and molasses as a source of six-carbon sugars. In addition, fermentation kinetics was investigated, the essence of which was to identify the technological parameters that allow the highest values of the main functions describing the process (AA, TPC LAe). Two kinetic models were used to determine the kinetics of process function changes during fermentation. The most favourable fermentation conditions for maximum antioxidant activity (26.88 mmol Tx/L ± 0.19), total polyphenol content (5.96 mmol GA/L ± 0.19), and lactic acid efficiency (88% ± 1) were: type of microorganism L. rhamnosus MI-0272, initial sugar content 3.20%, plant raw material content 6.40%, and a fermentation time of 9 days. The values of chelating activity (ChA), AA, and TPC in the fermented stems increased more than two-fold compared to the non-fermented extracts. Reducing activity (RA) and LAe increased to 46.22 mmol Fe3+/L ± 0.29 and 88% ± 1, respectively. Of the kinetic models adopted, follow-up reaction equations and first-order equations best described the time-dependent changes taking place. This study shows that the process function values of AA and LAe are dependent on the LAB strain and the content of the plant material, and the rate of change of TPC may largely depend on the forms of phenolic compounds formed during fermentation.

Formation of Corrosion‐Resistant Nitride Coatings Based on Ti–Al–Cr–Fe–Ni High‐Entropy Alloy

The purpose of the work is to study the features of the phase and structure formation of coatings (Ti–Al–Cr–Fe–Ni)N formed by vacuum arc deposition and to study the influence of technological parameters of the deposition process on their corrosive properties. It is established that on the basis of the selected elements, it is possible to form a high‐entropy compound in the form of a solid solution. The structure of nitride coatings based on high‐entropy compounds formed by vacuum arc deposition is studied. It is established that the phase composition of coatings largely depends on the ratio of titanium and aluminum, which is determined by the technological parameters of deposition. An analysis of the results of the electrochemical behavior of coatings (Al,Ti,Fe,Cr,Ni)N shows that an increase in the corrosion resistance of these coatings is due to the synergistic effect of the formation of a solid substitution solution with a dense nanoscale structure and an increased relative aluminum content in them.

ТЕХНОЛОГІЇ ХОЛОДНОГО РЕСАЙКЛІНГУ ДЛЯ ГЛИБОКОЇ РЕГЕНЕРАЦІЇ НЕЖОРСТКОГО ДОРОЖНЬОГО ОДЯГУ

ntroduction. In the introduction to the article, the briefly performed comparative analysis of the road asphalt concrete cold recycling technologies was adduced and also the actuality of the implementation of widened nomenclature of such technologies in the Ukraine was outlined. Problem statement. The issue of the article concerns processes and materials for technologies of the full-depth reclamation of flexible road pavements using cold recycling trough full depth of asphalt layer/layers including the underlying layers of granular materials as required. Purpose. The aim of the article is to analyze the technological parameters of processes of full-depth reclamation (FDR) and also general requirements for reclaimed materials especially those concerning the estimation of their thermorheological properties. Results. The methods of the reclaimed materials stabilization were examined which, in accordance with the FDR technologies, should be divided in mechanical and those performed with the stabilizing agents. The types of pavement defects were defined under presence of which the application of FDR technologies has been recognized highly effective. The concise analysis of general requirements for reclaimed materials was performed with setting off the materials subjected to special requirements for grading. Also, the technological particularities of processes of the full-depth reclamation were stated which should be attributed to the technical characteristics of road equipment, the road pavement condition, and reclaimed mixtures quantitative proportions as well. According to the analysis of the test methods of reclaimed materials stabilized by bitumen using foamed bitumen, the role of the thermoreological uniformity of cold recycled mixtures for their proper design was shown.