Methods of pressure treatment of metals based on the action of technological load in the conditions of a localized plastic cell. The main purpose of such methods is that the change in shape at any time is performed only on a fraction of the volume of the workpiece and when moving the deformation center covers the entire volume. These are well-studied and widely used in the production of free forging, rotary forging, rolling, etc. A relatively new method of MP - stamping by rolling, is characterized by a number of positive effects: - reduction of deformation force in comparison with traditional methods in 5-30 times; - the possibility of processing metal in the cold state with the same technological effort as in hot processing; - the equipment corresponds to a high level of labor safety; - reducing the size, weight and cost of equipment; - the possibility of implementing various technological operations. Modern mechanical engineering, instrument making and other metalworking industries widely use and manufacture parts with a large ratio of cross-sectional dimensions, the production of which by existing methods of metal forming is either inefficient or impossible. The most technological are the processes of SHO, in which the workpiece has a tubular or annular shape. Such blanks are well amenable to induction heating, which while providing a high frequency electromagnetic field allows them to be heated quickly and efficiently. This can heat a limited amount of workpiece material. Thus, the use of induction heating in the processes of SHO significantly expands their technological capabilities, which determines the relevance of the chosen topic. The main advantages of induction heating include: transmission of electrical energy does not require contact devices, is carried out directly into the workpiece, which increases the heating rate; due to the possibility of controlling the frequency of the current, the maximum power is released in the limited thickness of the surface layer of the product, which is especially effective when heating the pipe blanks; induction heating can increase productivity and improve working conditions.
The processes of planting blanks by the rolling stamping method allow for the efficient production of a wide range of high-quality products, but the possibility of material destruction during deformation prevents the expansion of their technological capabilities. Further development of the processes is possible through the development of new technological schemes based on the analysis of deformation kinematics and the appointment of favorable technological parameters, taking into account their influence on the stress-strain state and deformability of the material of the workpieces. In order to widely use the method of assessing the deformability of workpieces, a reliable technique is needed, which provides for the presence of a mathematical model of the trajectory of deformation of material particles in the coordinates "stress state indicator - accumulated plastic deformation before failure." The work uses an approach to finding an analytical representation of the deformation trajectory based on the construction of a differential equation between the components of plastic deformation increments, followed by the solution of this equation and the identification of its parameters based on experimental data. According to the results of the research, the deformation trajectories of the material particles of the peripheral surface of the flange when planting by rolling stamping method were schematically constructed in the coordinates "intensity of deformations - stress state indicator". Based on the built model, damage accumulation can be simulated by changing the values of the model parameters for different materials and deformation paths. An analytical representation of the deformation trajectory in a parametric form was obtained. The advantages of representing the deformation trajectory in the form of parametric equations are the convenience of analyzing these trajectories. The advantage of the model of the trajectory of deformation of material particles in the coordinates "stress state indicator - plastic strain accumulated before failure" is the absence of a material constant in the analytical expression for the stress state, and the consequence is additional convenience of analyzing ratios and selecting the value of the material constant based on experimental data.
This article is devoted to the equipment for gas-dynamic spraying in order to simplify its design, to provide the possibility of adjusting the parameters (temperature, pressure, speed, ejection) of the air-polymer flow, and to clarify the fundamental possibility of creating polymer functional coatings with gas-dynamic spraying. The polymeric materials, depending on their brand, are completely inert and do not react in any chemical reaction with food, animal waste products, acids and other corrosive media. It is known that polymeric materials can be attributed to the two main classes of reactants and thermoplastics. If the thermoplastic process of heating and cooling can occur repeatedly without changing their structure, then reactive plastics with a single heating with increasing time of elevated temperatures as a result of chemical processes occurring in them, transform into an insoluble solid state with the formation of a mesh structure of macromolecules. This process is irreversible, the products of the reactoplasts are destroyed by reheating at a sufficiently high temperature without first softening and thus cannot be recommended for their use in order to create polymer coatings by gas-dynamic sputtering. The characteristics of the most common thermoplastics, such as polypropylene, polyethylene, polytetrafluoroethylene, polystyrene, polyvinyl chloride, polyamides, are analyzed, and the conditions to be created for the successful application of functional polymer coatings. Experimental application of polymer coatings of the most common polymers. The results obtained indicate that the designed and manufactured prototype gasdynamic spraying device is capable of creating different modes of polymer coating. That is to change and maintain the required temperature and pressure of compressed air. The results of the researches show a fundamental possibility to create polymer coatings from thermoplastics on metal surfaces by gas-dynamic spraying.
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