Manufacture Of Machine Parts Research Articles

On the effectiveness of using carbamide-based salt baths for low-temperature cyanidation of improved carbon and alloy steels

Purpose. A study of cyanidation of improved carbon and alloy steels of grades 30, 30HGT, 30H13 at a temperature of 550–580 °C was carried out in baths based on carbamide and sodium carbonate. Recommendations on the use of these baths for surface hardening of carbon and alloyed improved steels used for the manufacture of machine parts are formulated. Methods. The microstructure of the diffusion layer of steels on transverse sections was studied using a Quanta FEG – 650 electron scanning microscope with an EBCD focused ion beam microanalysis system. Cyanide wear tests were performed under friction conditions analogous to those of die tools. The wear resistance of the carbonitrided samples was investigated on a SMTs-2 friction machine. The tests were performed under both dry friction and boundary friction conditions. Results. The high efficiency of the proposed bath composition at a given temperature has been experimentally shown. As a result of cyanidation, modified layers saturated with solid inclusions (ε-phases) are formed on the surface of steels, characterized by high hardness, low coefficient of friction and high wear resistance. Conclusion. According to the results of the conducted research, it can be concluded that low-temperature cyanidation of improved steels of various grades can be carried out in cyanide-free salt baths. The optimal composition of the cyanide bath is 40% carbamide (NH2)2CO; 40 % soda ash Na2CO3 and 20 % NaCl table salt. The proposed bath does not contain toxic and scarce components, therefore it is environmentally safe and very cheap and can be used with great effect in machine-building, repair and tool industries.

Applications of HSS alloys for the production of planetary core cutting heads for tapping holes

This article provides for the possibility of manufacturing crown cutters from foreign-made high-speed steel HSS, which is not inferior to other similar alloys. The article presents the geometric parameters for the manufacture of a new crown cutter and its use in the field of mechanical engineering for cutting holes in the manufacture of machine parts and rolled products. An example is also given of connecting new pipeline lines to an existing pipeline, which is under pressure up to 2.5 MPa, in heat supply and water supply networks. Methods for eliminating vibration when cutting holes on pipes and rolled products using special lubricating coolants are considered. An example of an invented device design is given that cuts holes in pipeline networks used under pressure up to 25 MPa in hydrometallurgical plants for gold mining and in the chemical and oil industries. A practical example of replacing expensive (tungsten) carbide alloys with foreign highspeed alloys HSS is also presented.

Fluid–structure interaction of a dynamic seal with a 3D‐printed surface

AbstractAdditive manufacturing (AM) methods are finding more and more applications in the manufacturing of machine parts. One consequence of this method is that generated surface qualities are typically lower than in other processes. This becomes especially relevant when the surface quality is critical for the mechanical function: This is the case in dynamic sealing technologies, for example, in seals between a moving rod and a hydraulic cylinder. Between the seal lip and the polished rod, a thin lubrication film is established with the goal of minimal leakage. How well this goal is reached depends on the surface quality of the seal. For spare part production of seals, we investigate AM methods, which have a surface defined by layers from fused filament fabrication (FFF). We apply a coupled model for fluid–structure interaction of the elastic seal and the film flow. This model provides information on flow field and pressure distribution. Results change when the ‘ideal’ seal lip is replaced by the seal lip geometry from FFF. The continuous loss of solid body contact is replaced by a stepwise loss of contact for the FFF surface.

Analysis of tool wear and surface roughness in machining of AISI 4462 duplex stainless steel

Abstract Machining is one of the most precise manufacturing methods used in the manufacturing of machine parts. In machining, significant tool wear is observed due to cutting tool-to-workpiece contact. Controlling tool wear and minimizing the effect of tool wear in this method is an important research topic. In this study, machinability tests were carried out on AISI 4462 duplex stainless steel materials, which are in the hard-to-cut material class. In the experiments, the changes in tool life and surface roughness were analyzed by using 150, 180, and 210 m/min cutting speeds; 0.1 mm feed; and 0.8 mm depth of cut. Increasing cutting speed significantly increased wear and reduced tool life. However, experiments with cutting speeds of 180 m/min and 210 m/min had the same tool life values. In addition, significant notch wear and BUE formation were observed on the tool surface. Besides, it was determined that the surface roughness deteriorated due to tool wear. In addition, surface deterioration due to chip wrapping was also observed in many passes.

Study of the effect of shock wave loading on the structure and properties of bronze alloys BrAZh9-4 and BrAMts9-2

Bronze alloys, due to their resistance to mechanical abrasion and high corrosion resistance, are used for the manufacture of machine parts and mechanisms that are subject to friction during operation. We present the results of studying the effect of shock-wave loading on the structure and properties of bronze alloys of grades BrAZh9-4 and BrAMts9-2. Shock-wave loading experiments were carried out by throwing the flyer plate onto cylindrical samples and compressing by a sliding detonation wave. The method of throwing a flyer plate accelerated by the energy of an explosion is often used to determine the spall strength of materials and the method of compression by a sliding detonation wave is used to create a large dynamic pressure inside the material. It is shown that at a throwing speed of a flyer plate of 2.4 km/sec, the impact pressure of the plate with the sample is 15 – 16 GPa, which exceeds the bronze shear strength. Under indicated loading conditions, the hardness of bronze increases by 53 and 25% for BrAZh9-4 and BrAMts9-2, respectively. Studies of the microstructure using scanning electron and optical microscopy revealed multiple cracks and micropores present on the surface of transverse sections forming a zone of spall fracture and areas turning into bands of localized deformation. Moreover, it is shown that when the samples are loaded with a flyer plate in a clip and without it, a greater number of cracks and shear areas are observed. Compression by a sliding detonation wave with a different amount of explosive charge revealed small defects present in the structure at the grain boundaries. The results obtained can be used to developed technologies for modifying and restoring the properties of bronze parts subject to shock-wave destruction.

Changes in Abrasion Resistance of Cast Cr-Ni Steel as a Result of the Formation of Niobium Carbides in Alloy Matrix

Cast austenitic chromium-nickel steel is commonly used for the manufacture of machine parts and components, which are exposed to the attack of corrosive media and abrasive wear during operation. The most commonly used grades include GX2CrNi18-9 and X10CrNi18-8 as well as GX2CrNiMo17-12-2 and X6CrNiMoNb17-12-2. To improve the abrasion resistance of cast chromium-nickel steel, primary niobium carbides were produced in the metallurgical process by increasing the carbon content and adding Fe-Nb. The microstructure of the obtained test castings consisted of an austenitic matrix and primary niobium carbides evenly distributed in this matrix. The measured hardness of the samples after heat treatment ranged from 215 to 240 HV and was higher by about 60 units than the hardness of the reference cast GX10CrNi18-9 steel, which had a hardness of about 180 HV. Compared to the reference cast steel, the abrasive wear resistance of the tested cast chromium-nickel steel (measured in Miller test) with contents of 4.4 and 5.4 wt% Nb increased only slightly, i.e., by 5% for the lower niobium content and 11% for the higher niobium content. Compared to ordinary cast GX10CrNi18-9 steel, the addition of 9.2 wt% Nb reduced the abrasive wear by almost 2.5 times.

Algorithms for program control of technological parts manufacturing process

Algorithms for program control of the technological process of manufacturing parts used in mechanical engineering are proposed. The software is based on a functional subsystem corresponding to optimization methods. The technological process is presented in the form of algorithms, blocks, tasks and settings. Technological procedures for the manufacture of machine parts are analyzed. The parameters for setting the control cyclograms are shown, which are aimed at creating unified software and means of operational adjustment for specific tasks in the manufacture of machine parts, which ensure the accuracy of processing with minimal time costs. Keywords unified algorithm, technological procedure, optimization, mathematical model, operation, setting parameter, specification level

On issue of selecting of ion implantation dose for activating of surface layer of alloy steel parts before nitriding

The article discusses the method of selecting ion irradiation doses for high-energy activation of the surface layer of alloy steel parts before nitriding. A criterion is proposed for optimizing the radiation dose of implanted ions from the strength limit of plate samples with a thickness commensurate with the thickness of the nitrided layer at implantation energies that ensure their end-to-end activation. The results of tests for rupture of plate samples with a through nitrided layer are presented. The results of comparative wear tests of samples made of alloy steels with nitrided layers used for the manufacture of machine parts operating under conditions of wear friction are presented. It is shown that the use of the method of selecting the dose of nitrogen ion irradiation with high-energy activation of the surface of samples made of alloy steels 40X and 40HN, allows to increase their wear resistance by approximately 1.3—1.4 times.

ВИКОРИСТАННЯ ЕНЕРГОЗБЕРІГАЮЧИХ ТЕХНОЛОГІЙ У ВАЖКОМУ МАШИНОБУДУВАННІ

Modern mechanical engineering is characterized by high energy consumption, which specific share of cost can reach from 15 to 25%. The task is to research energy-efficient technological methods of mechanical processing, which will reduce the cost and duration of the production cycle.As a criterion for optimizing the machining process, it is proposed to use quantitative indicators of the specific energy intensity of cutting. The feasibility of using energy-efficient strengthening methods in the technological process of manufacturing parts in heavy engineering needs to be studied.The purpose of the work is to study the use of energy-saving technologies in the manufacture of machine parts in heavy engineering.It is proposed to use a mathematical model to determine the optimal technological parameters of energy-efficient processes of mechanical processing of heavy engineering parts. The level of energy consumption in the cutting zone, which is spent on removing a given volume of material from the layer of the workpiece being cut, is best reflected by the specific energy intensity of cutting.To ensure the operational properties of machine parts, it is proposed to use methods of surface strengthening with the use of electric current.The use of finishing turning with electric pulse heating in the manufacturing process of the shaft allows to replace four operations -turning, heat treatment, two circular grinding operations -with one operation.Clean turning with electric pulse heating has such advantages as: the possibility of strengthening the surface layer of the part by differentially wearing it (for parts that wear unevenly); processing on one technological equipment; reducing the number of technological operations; low equipment costs.It was determined that the introduction of processing methods using electric current, in particular, turning with electric pulse heating, allows to significantly reduce the duration of the production cycle of manufacturing parts of heavy engineering. The amount of energy consumed can be reduced by 80%

Increasing of wear resistance of machine parts by nitriding while suppressing of nitride mesh formation process

The article discusses the technology of nitriding machine parts made of alloy steels, which provides suppression of the nitride mesh formation process as a result of preliminary two-stage preparation of the surface layer for nitriding, including obtaining a surface layer of a material with an ulramelkodisperse structure followed by high-energy implantation with nitrogen ions. Comparative models of the formation of nitrided layers obtained with traditional and proposed nitriding methods, as well as models of wear under conditions of friction of the surfaces of parts, are proposed. The results of comparative wear tests of alloy steels with a nitrided layer used for the manufacture of machine parts operating under conditions of wear friction are presented. It is shown that the absence of a nitride mesh in the nitrided layer increases the wear resistance of the nitrided layer by approximately 3—4 times.

INFLUENCE OF NITROCEMENTATION MODES ON THE CHANGE IN THE HARDNESS OF THE SURFACE LAYER OF STRUCTURAL STEELS

This article provides research on the influence of technological modes of nitrocarburizing carried out in a paste-like carburized on the change in the hardness of the surface layer of steels of grades 40 and 40X. These steel grades are the most used in the manufacture of machine parts in which surface hardness is the determining factor in the wear resistance of steel.

Prospects for the application of the product life cycle system by means of the planned preventive maintenance module on the example of aviation and agricultural components

The paper describes an approach to the development of a functional software module within the subsystem of planning, rationing, preventive, routine maintenance, with the functions of accounting for the time of turning operations in the manufacture of machine parts for various purposes, in the general technological chain of the software complex of interacting ERP/MRP/CAD/CAM/CAE technologies of the enterprise, including forecasting both the time of resource operation and the production of necessary components, in order to support manufactured aviation, agricultural and other products throughout the life cycle.

Application of wire arc additive manufacturing for repair of Monel alloy components

ABSTRACT Monel alloys containing 63Ni-30Cu-2.0Mn-2.0Fe-AlTiC (wt. %) are often used for manufacturing of machine parts in marine, chemical, and oil extraction industries. Despite excellent corrosion resistance and mechanical properties, Monel components may fail via wear, which is enhanced in corrosive environment. Heavy components working under high loads may experience galling, which is welding followed by tearing of large pieces of material off the contacting surfaces. In addition to high cost of Ni-based alloys, heavy parts of machinery may not be easily replaced, and, thus, require repair being in partial assembly. In this paper, we introduce wire arc additive manufacturing (WAAM) technology as a repair method for Monel alloy components. The effect of post-weld heat treatment on microstructure and hardness of both the component body and the repair layer is investigated and discussed.

Output parameters at development and production stage of a product in its life cycle

The priority of research into modern information systems for controlling technological processes of product manufacturing and their introduction into the practice of machine-building enterprises is established. Described the object-oriented and functionally-oriented principles of designing technological processes in the manufacture of machine parts and the area of their effective use. Algorithms of initial product parameters formation when implementing object-oriented and function-oriented principles of technological processes design are analyzed. A generalized algorithm of a CAF-system functioning in the structure of an integrated design-engineering preproduction is presented. The conditions of shaping product parameters taking into account the influence of an integrated subsystem of design-engineering preparation of machine-building production and technological subsystems: machine, fixture, tool, workpiece are analyzed. The main provisions of the system approach to the study of the formation of the output parameters of products at the stage of their creation in life cycles during the implementation of function-oriented design principles are formulated. The conditions for the realization of physical processes from the position of the synergetic approach in the study of technical systems are analyzed. A mathematical model for predicting the probability of forming a workpiece blank without defects at the stage of its creation during the implementation of the technological process of product manufacturing was developed. Numerous solutions of the mathematical model are given, which determine the degree of influence of technological subsystems on ensuring output parameters of the product. Using a synergetic approach, the process of forming the initial parameters of the product as a result of interaction between the integrated subsystem of design-engineering preparation of engineering production and technological subsystems: machine, device, tool, workpiece with the provision of quality control parameters of the product using the CAF subsystem and a subsystem of implementation of control operations. Further research will concern the development of algorithms for determining the solutions of mathematical models when designing technological processes for the manufacture of machine parts using a function-oriented design principle while ensuring the regulated quality parameters of their executive surfaces.

Разработка автономных программных решений на основе геометрических ядер по созданию цифровых сборочных моделей станочных приспособлений

The article discusses approaches and solutions aimed at increasing the productivity of engineering departments, where CAD software solutions are actively used. In the manufacture of machine parts, it becomes necessary to design technological equipment. Elements of machine tools can be prepared and placed in electronic catalogs (libraries), which in an automated mode will create a set of parametric models of the required technological equipment of machine tools. In this case, the accuracy and quality of modeling will be achieved by excluding the human factor from the design process. The development of such software solutions is implemented by means and components of the open geometric kernel Open Cascade, which has great potential both in the field of modeling and scientific computing.

Application of the Polymeric Material RIMAMID for Production of Machine Parts

Modern polymeric materials have properties that, in some respects, exceed the properties of traditionally used materials (steel, aluminum and titanium alloys, wood). The uniqueness of the Rimamide polymer material is that it is possible to pre-design the material in such a way as to give the product from it the properties necessary for a particular application.The production of blanks and the use of Rimamide material for the manufacture of sliding and rolling bearings, bushings for wheels and rollers, pulleys, blocks, brackets, wheel hubs, gears, sprockets, gears and worm wheels and other parts to reduce weight, noise and vibrations. The characteristics of the material, examples of the manufacture of blanks, the advantages and disadvantages of the RIMAMID material for the manufacture of machine parts, prospects for use in mechanical engineering are shown.Due to their properties, they can be used in almost all industries. For example, modern aviation and space technology is characterized by the intensive use of new materials, technologies, and promising designs based on them. When using RIMAMID material using antifriction components (molybdenum sulfide, graphite, etc.), the friction coefficient is significantly reduced and the friction units can be operated without lubrication.The main advantages of this material is a low coefficient of friction for steel, which provides a 3-4-fold increase in the service life of parts in the friction units, as well as low weight, high strength, good machinability on metal cutting machines, resistance to aggressive environments, and environmental safety.

Basic principles for describing the process of vibratory with an external source of dynamic impact

The modern development of mechanical engineering requires high quality manufacturing of machine parts. The production experience testifies that high requirements to the quality of surface treatment of the parts need to be improved, in particular, in the finishing and clearing operations (FCO). Progressive method of processing parts is vibratory (V) on machines with U-shaped containers. Despite the positive practical experience of vibratory using in mechanical engineering, this method faces a number of problems related to the development of its theoretical foundations: equipment and tools are still imperfect; in the initial stage are works on managing of the V process; it is insufficiently studied the mechanism of surface layer formation at V. These problems hamper further development and improvement of the vibratory, which is very effective by its technological capabilities, and limit its wider introduction into industry. Efficiency of processing is provided by the right choice of equipment, schemes, and modes of processing, types of working environments. The mass of loading in the container of the machine does not absorb all the energy transmitted by the vibratory machine, but only part of it, the other part is non-productively dissipated. Therefore, the choice of the constructive scheme of the machine, on which the redistribution of these energies depends, is a crucial step, both in its design and in the management of the machining process.

Microanalysis of Additive Products from Electro-Erosion Cobalt-Chrome Powders

The results of microanalysis of additive products from electro-erosive cobalt-chrome powders are presented. It has been established experimentally that the obtained samples of additive products from powders, obtained by electro-erosive dispersion of cobalt-chrome wastes in alcohol, have a microcrystalline structure with a porosity of less than 0,78%. The obtained experimental data can be used in the development of promising resource-saving technologies for the manufacture of machine parts.

Production of blanks and parts of machines from polymeric material "Rimamid"

The production of blanks and the use of material "Rimamid" for the manufacture of sliding and rolling bearings, bushings for wheels and rollers, pulleys, blocks, brackets, wheel hubs, gears, sprockets, gears and worm wheels and other parts to reduce weight, noise and vibrations is considered. The characteristics of the material, examples of the blanks manufacture, the advantages and disadvantages of the material "Rimamid" for the manufacture of machine parts, prospects for use in mechanical engineering are presented.

Evaluation of microgeometry of cylindrical parts after cross-rolling in smooth plates

Hardening and finishing processing of cylindrical parts by transverse rolling in smooth plates was studied. The effect of the relative deformation and rotational speed of the workpiece on the main quality characteristics of the surface layer of hardened parts, such as diameter accuracy, roughness and ripples of the surface layer was determined experimentally. The results of the work offer a means for adopting the described method of cross-rolling for manufacturing of machine parts. The process in question can be implemented without the use of environmentally hazardous lubricating cooling technological means, which makes it possible to attribute it in the future to one of the types of green mechanical processing technologies.