Issue №: 2(101)
The journal deals with the problems of vibration technologies and machines, mathematical methods of vibration process studies, information on design and technological development, presents teaching and methodological aspects of teaching in the Higher School of Applied Sciences, where vibration machines and technologies are studied.
APPLICATION OF CURRENT LINES IN DETERMINING KINEMATIC CHARACTERISTICS IN STATIONARY PROCESSES OF PLASTIC FLOW OF METAL
Sivak Roman - Doctor of Technical Sciences, Associate Professor of the Department of General Technical Disciplines and Labor Protection of Vinnytsia National Agrarian University (3 Sonyachna St., Vinnytsia, Ukraine, 21008, e-mail: sivak_r_i@ukr.net)
Нunko Iryna - Candidate of Technical Sciences, Associate Professor of the Department of General Technical Disciplines and Labor Protection of Vinnytsia National Agrarian University (3 Sonyachna St., Vinnytsia, 21008, Ukraine, e-mail: irynagunko@vsau.vin.ua).
Zalizniak Roman - graduate student of the Department of General Technical Disciplines and Labor Protection of Vinnytsia National Agrarian University (3 Sonyachna St., Vinnytsia, Ukraine, 21008, e-mail: pacifistroma@gmail.com)
Methods of theoretical solution of problems in the processing of metals by pressure are insufficiently developed for practical use in the development and implementation of new technologies and improvement of existing ones. To meet the stringent requirements for the accuracy of determining the stress-strain state, it is necessary to have reliable information about the evolution of the development of the plastic deformation process at each point of the metal from the very beginning of the deformation. This will allow to obtain with high accuracy the important characteristics of the technological heredity of the products that they acquire as a result of their plastic processing. The first and important step in the calculations of the stress-strain state is to obtain the kinematic characteristics of the plastic flow of metal in the form of analytical dependences, which will formulate the patterns of deformation in the technological processes of metal forming.
The article considers the possibility of applying the method of current functions to determine the components of the strain rate tensor in established stationary processes of plastic deformation. It is assumed that in the case of axisymmetric plastic deformation of a metal in a channel with curvilinear boundaries, the kinematics of the process is similar to a plane flow. In obtaining the equations, the differential equation of current lines taking into account the incompressibility condition was used to determine the components of the strain rate tensor. To explain the physical meaning of the current functions, two infinitely close current lines were considered in the flow plane, and an expression was obtained for the flow through a finite transverse current tube. In the absence of radial velocity components at the boundaries, constraints are obtained that are imposed on derivatives of current functions at these boundaries. The developed method of calculating the kinematic characteristics of plastic deformation for established axisymmetric stationary processes will simplify the mathematical processing of the obtained results and increase the reliability of the determination of the stress-strain state.
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2. Kurin M. А. Issledovanie metodom giperbol obtekania klina pri svobodnom rezanii. Metalofizika. Noveishie tehnologii. Fizika prochnosti i plastichnosti. Harkov. 2018. №7, т. 40. S. 859-876.
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4. Beygelzimer Y., Reshetov A., Synkov S., Prokof’eva O., Kulagin R. Kinematics of metal flow during twist extrusion investigated with a new experimental method. Journal of materials processing technology. 2009. Vol. 209, issue 7. P. 3650-3656.
5. Ogorodnikov V. А., Derevenko I. A., Sivak R. I. On the Influence of Curvature of the Trajectories of Deformation of a Volume of the Material by Pressing on Its Plasticity Under the Conditions of Complex Loading. Materials Science.Vol. 54, 2018. P. 326-332.
6. Sivak R. Evaluation of metal plasticity and research of the mechanics of pressure treatment processes under complex loading. Eastern-European Journal of Enterprise Technologies. Kharkiv. 2017. №6/7 (90). P. 34-41.
About the journal
The journal "Vibrations in Engineering and Technologies" is included in the list of technical scientific publications of Ukraine
(Category "B", Order of the Ministry of Education and Science of Ukraine dated July 2, 2020 No. 886)
Old version of the site: http://vibrojournal.vsau.edu.ua/
The journal "Vibrations in Engineering and Technology" is indexed by the following databases and catalogs:
The certificateof massmedia State registration:kv no 16643-5115 from 30.04.2010 .
Founder of the journal: Vinnytsia National Agrarian University
The journal is devoted to highlighting current issues in engineering, mechanical engineering, and technological processes, including the study of dynamic and oscillatory phenomena in technical systems, the application of mathematical methods for process modeling and analysis, as well as the presentation of results of design-engineering and technological developments. Particular attention is given to the study of vibration processes and their application in modern technologies.
The purpose of the scientific journal “Vibrations in Engineering and Technologies” is to disseminate the results of fundamental and applied research in the field of engineering sciences aimed at developing theoretical foundations and practical approaches to the design, analysis, and improvement of machines, materials, and technological processes, including the use of vibration and oscillatory effects in various sectors of production.
The publication is focused on the formation of a modern scientific and informational environment for the effective exchange of research results, support of innovative development, and implementation of advanced technical solutions in industry, agro-industrial production, and related fields.
The journal promotes the development of interdisciplinary research, the integration of modern engineering approaches, and the enhancement of the efficiency of technological processes and technical systems, including through the rational use of vibration phenomena.
Objectives of the Scientific Journal
To achieve its stated purpose, the journal addresses the following key objectives:
dissemination of results of fundamental and applied scientific research in the fields of mechanics, mechanical engineering, technological processes, machine dynamics, and equipment, as well as in areas related to the application of vibration phenomena in engineering and technologies;
promotion of research aimed at the creation and improvement of machines, mechanisms, and technological equipment based on oscillatory and vibration processes;
support for the implementation of modern technological solutions focused on improving productivity, energy efficiency, and reliability of technical systems;
обеспечение scientific exchange of research results among research institutions, higher education establishments, and industrial enterprises;
development of interdisciplinary cooperation among researchers in the fields of mechanics, materials science, material processing technologies, and automation of technological processes;
dissemination of modern scientific achievements and advanced technologies related to the application of vibration processes in production and technical systems.
Publisher Vinnytsia National Agrarian University
In June 1994 the 2nd International Scientific and Technical Conference "Application of vibrations for technological purposes" was organized on the basis of Vinnytsia State Agricultural Institute. Leading experts in this field, noting the significant contribution to the school of Vibration Engineering under the leadership of P. S. Bernyk, proposed to create a professional all-Ukrainian scientific and technical journal "Vibration in engineering and technology..The journal was foundedat Vinnytsia State Agricultural Institute and P.S. Bernyk was elected to be the chief editor .
For all these years (since 1994) theJournal "vibration in engineering and technology" published 119 issues wherestudy of vibration effects, the creation of progressive energy saving technologies and equipment for their implementation were highlighted.
Currently Ihor Kupchuk, Candidate of Technical Sciences, Associate professor, Associate Professor of the Department of Engineering Mechanics and Technological Processes in the Agricultural Industry Faculty of Engineering and Technology Vinnytsia National Agrarian University is the chief editor of the "Vibrations in engineering and Technology"
The journal "Vibration in Engineering and technology", which has no analogues on the territory of Ukraine, is well known abroad.
