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Information × Registration Number 0218U003283, 0116U002657 , R & D reports Title Development of plastic processing methods and the creation of high-performance manufacturing processes profiles of aluminum-based alloys with a specific strength of more than 120 m2/s2. popup.stage_title Head Frolov Iaroslav Viktorovich, Registration Date 30-01-2018 Organization National Metallurgical Academy of Ukraine popup.description2 The object of research is the processes of plastic deformation of aluminum alloys. The subject is the regimes of plastic deformation of aluminum-based alloys. The purpose of the work is to improve the deformation modes and develop a technology for obtaining products from aluminum-based alloys with a specific strength of more than 120 m2 / s2 by determining the regularities of the effect of deformation parameters of plastic deformation processes on metal shaping and energy-strength parameters with the predicted level of mechanical properties. The main tasks of the project include: - Theoretically and experimentally investigate the complex effect of free forging operations (sediment operations with subsequent pulling / pulling operation) on the mechanical properties and structure of the product; - to develop the modes of preliminary pressure treatment by free forging operations of the selected alloy for research in order to eliminate the structural heterogeneity and increase the mechanical properties of the initial preform before subsequent deformation; - theoretically and experimentally (with the help of numerical methods) to determine the regularities of the influence of the geometric and temperature parameters of the pressing process on the mechanical properties and energy intensity of the process; - improve the temperature of the deformation parameters of the hot pressing process in order to improve the accuracy of the press products; - Calculate and experimentally determine the energy-strength parameters of pressing of these products; - to develop a technology for the production of products from the selected alloy, taking into account the pre-treatment of the pressure of the initial billet and improved compression regimes; - determine the shape of the material during hot rolling of the headquarters, determine the effect of the strain and temperature parameters on the mechanical properties of the material. The stated task is solved by the fact that the improvement of the structural heterogeneity in the preforms during direct pressing is carried out by performing pre-treatment by pressure, namely, performing free forging operations instead of high-temperature long-term homogenization treatment. The modes of using the free forging operations of the workpiece before subsequent direct pressing are developed, which ensure the reduction of the grain size of the metal, is deformed, and the metal structure is homogenized in the cross section of the workpiece due to the fact that in the successive operations of free forging "deposition" and subsequent "pulling" intensive accumulation of alternating deformation in the volume of the workpiece. In the course of the work, known methods of conducting a full-factor experiment were used. Theoretical studies were carried out in the QForm software complex, which uses the finite element method and is based on known regularities of the theory of the plastic flow of solids. All studies include four main components: theoretical, experimental research, analysis and comparison of data obtained, development of recommendations. The structure of theoretical studies is the definition and specification of boundary conditions for modeling plastic deformation processes, preparation of initial data for modeling, processing of simulation results. Experimental studies will include the development of an experiment plan, the preparation of samples and equipment, the implementation of the research plan and the processing of the data. For the first time, taking into account the rheological properties of the alloy of the Al-Mg-Sc system, the characteristics of the stress-strain state and the metal temperature in hot free forging operations, namely, the operation of draft and drawing, were determined theoretically using computer simulation methods. The difference in the development lies in taking into account the rheological properties of this alloy at the temperature of the high-speed conditions inherent in the processes of hot OMD. This allows us to clarify the location of zones with voltages dangerous for the integrity of the metal and temperatures. Analysis of the logarithmic deformation makes it possible to evaluate the workings of the billet. Information on the theoretically determined regularities of the effect of speed and temperature-deformation modes has been developed in the case of direct hot pressing of pipes from an Al-Mg-Sc system of an important-deforming aluminum alloy. The development is characterized by the fact that the data are obtained for the case of direct hot pressing of pipes on a mandrel with the ratio D / S = 4 ... 8 and with an extractor coefficient of 100. This allows predicting the pressing force when developing the technology of manufacturing finished profiles, choosing press equipment and increasing productivity of the press line. Further development was made about the effect of temperature and deformation rate, geometric parameters of the deformation zone on the force during rolling the headquarters for an important deformable aluminum alloy of the Al-Mg-Sc system. The development is characterized by the complex effect of rolling factors on the force of the process in the range 360-420 ° C and the ratio of the dimensions of the billet b / h = 1 ... 3. This allows us to predict the rolling force in the development of the manufacturing technology of headquarters, to choose the rational distribution of deformations along the rolling mill. As a result of the work, regression dependences were constructed, which allow not only qualitative but also quantitative assessment of the effect of the parameters of the sedimentation and broaching process and their joint effect on temperature parameters. When analyzing the hardness indicators of the above samples, it can be seen that the operation of free forging "Draft" at 40% deformation leads to an increase in hardness for the HL billet from 379 to 400, but when performing further operations of free forging "Feed" the hardness index for HL billet from 400 to 406 . This may indicate an increase in the mechanical properties of the sample. But this not very large increase in the hardness index indicates that material material does not materially materialize in the material of the billet. Received in the course of experimental studies and theoretical analysis of the rheology results of the Al-Mg-Sc alloy, it was possible to confirm the presence of a dynamic softening section, which is due to the active passage of dynamic recrystallization during hot plastic deformation. As a result of the work, regression dependences were constructed, which allow estimating the effect of deformation (in the range e = 15-35%) and temperature parameters (in the range t = 360-420 C) of the parameters of the longitudinal rolling process on the energy-force parameters of the process, namely the force and the rolling moment , and the geometric size of the staffs (extensions). In the process of research, the fact of obtaining seamless pipes of the necessary sizes and qualities is established. However, with the use of large drawing coefficients (> 40) and high extrusion temperatures (> 440 ° C), partial and sometimes complete destruction of the products occurred. The recommended processing parameters for the selected alloys are the following: - alloy 7075 - pressing temperature 440 ° C, pressing speed 0,5 mm / s, tool material - heat-resistant steel 1.3243; - alloy 2024 - pressing temperature 440 ° C; pressing speed 0.1 mm / s., tool material - heat-resistant steel of grade 1.3243; - alloy system Al-Mg-Sc (01570) - - pressing temperature 410 ° C, pressing speed - 1 mm / s, tool material - heat-resistant steel grade 1.3243. Evaluation of the results of measurements of mechanical properties shows that the hardness of the material is almost constant in the thickness of the wall. This observation applies to both the alloy type and all samples. In the state after pressing, all the measured hardness values of the selected alloys are in the range of 100-115 HV. In this case, the strength values are at a level, depending on the type of alloy and deformation features: the ultimate strength is 375 ... 390 MPa; yield strength - 220 ... 265 MPa; the relative elongation is 13 ... 18%. The data obtained within the framework of R & D, the data are of practical value and can be used in designing promising samples of pipe profiles for engineering and the color industry as a whole (an act on the use of research results from PJSC NUVF "PRECISIONETRUB-YUG"). Also, the results of the GDR studies on improving the regimes deformation and development of technology for obtaining products from aluminum-based alloys with a specific strength of more than 120 m2/s2 by determining the patterns of the influence of deformation parameters plastic deformation for metal shaping and energy-strength parameters with the predicted level of mechanical properties are used in the courses of lectures, practical and laboratory studies of NMetAU in the disciplines: "Theory of metal forming processes", "The technology of metal forming processes", "Modeling and optimization of metal forming"," Processes and machines for metal-forming, "" Technologies for metal-forming of non-ferrous metals and alloys, "" deformation-heat treatment of metals s and alloys ", as well as in carrying out the purposes of the processing of the department students of master and fishing pressure final works of bachelors (act of implementation of research results in the educational process of the department OMD them. acad. AP Chekmareva NMetAU from 11/09/2017). Under the guidance of Doctor of Technical Sciences, prof. Golovko A.N. according to the results of the research carried out by the research workers "Development of methods for plastic processing and creation of high-performance technological processes for the production of aluminum-based alloys with a specific strength of more than 120 m2/s2" at the Department of MFD NMetAU was created and handed over to use recommendations and proposals by concluding contracts for R & D for a total of UAH 1,200,000, namely: "Development of a technological task for the production of a seamless tubes made of titanium hollow billet"(code H12530007. Supervisor - PhD, Senior Scientist Medvedev MI). Product Description popup.authors Андреєв Віталій Валерійович Ашкелянець Антон Володжимирович Бобух Олександр Сергійович Бондаренко Сергій Валерійович Клемешов Евген Сергійович Коноводов Дмитро Володимирович Медведєв Михайло Іванович Панюшкін Євген Миколайович Самсоненко Андрій Анатолійович popup.nrat_date 2020-04-02 Close