Telyatnik I. Research into deformation strengthening of working surfaces of soil tillage machines by hydropulse loading

Telyatnik I.A. Research into deformation strengthening of working surfaces of soil tillage machines by hydropulse loading. – Qualification scientific work in the form of a manuscript. Dissertation for the educational and scientific degree of Doctor of Philosophy (PhD) in specialty 132 Materials Science (13 Mechanical Engineering) – Vinnytsia National Agrarian University, Ministry of Education and Science of Ukraine, Vinnytsia, 2026. The dissertation solves an important scientific problem related to increasing the wear resistance of the working bodies of soil-tillage agricultural machines. This was achieved through theoretical substantiation and determination of optimal design and technological parameters for strengthening the working surfaces of tillage implements by surface plastic deformation under hydraulic impulse loading. The introduction contains a justification for the importance of the research, a clearly formulated goal, and a list of specific tasks necessary to achieve it. The novelty of the obtained scientific results, the practical value of the work, and the author's personal participation in its implementation are highlighted. Information on the validation of the results, a list of publications, and a description of the structure and overall scope of the dissertation are provided. The purpose of the study is to increase the wear resistance of the working surfaces of soil tillage agricultural machinery bodies by surface-plastic deformation under hydraulic impulse loading. To achieve this goal, an analysis of known wear processes was conducted and the parameters and features of the application of surface plastic deformation methods to increase wear resistance were characterized. In the course of the work, a schematic diagram of a press with a hydraulic pulse drive was developed and a mathematical model of the operating cycle of a hydraulic pulse device for deformation hardening was created, and the shape change of the structure of polycrystalline materials during deformation was also investigated. In addition, an experimental stand with a hydraulic impulse drive for surface plastic deformation of parts was developed, which made it possible to experimentally establish the dependence of material hardness parameters on the operating modes of the hydraulic impulse equipment and the design parameters of the striker. The results of the study include the implementation of production implementations and the study of the regularities of the operating modes of the hydraulic pulse load. The object of research is the process of surface-plastic deformation of the working surfaces of the executive elements of soil tillage equipment under conditions of hydraulic impulse loading. The subject of the study is the relationship between the parameters of the formed surface layer and the technological modes of the process of surface-plastic deformation by hydropulse loading. The paper analyzes the features of wear of working parts of tillage machines in the conditions of modern agricultural production in Ukraine. Typical defects of the working parts of plows (shares, shelves, knives), cultivators (paws, racks) and disk harrows (disks) are presented, as well as permissible wear parameters (blunt width, toe length, back chamfer width), which are criteria for loss of performance and the need for repair or replacement.