The priority is given to carrying out studies to improve the performance characteristics of agricultural machinery parts in the context of modern technologies. The value of ultrasonic effects for the surface treatment of steel parts is established. The relevance of research is determined. The analysis of literature sources is carried out, the necessity of optimization of technological parameters of mechanical processing of materials with use of ultrasonic influence is shown. It is established that, mechanical processes that occur during the interaction of an ultrasonic working tool and the surface of a part are rather complicated. The expediency of studying specific aspects of the behavior of the machined material of parts on the basis of numerical modeling is determined. A model contact problem was formulated to study the processes of surface hardening during plastic deformation using ultrasound. The research tasks, boundary conditions are determined. Numerical simulation is carried out and ways of optimization of parameters of the considered technological process are described. The boundary value problem of the equation of motion, the Cauchy relation, the physical relationships of the components of the deformation components with the necessary boundary conditions are solved. As indirect characteristics, allowing to judge the level of strengthening of the material, residual plastic deformations were taken in the direction of the general axis of symmetry of the cylinder and the indenter. The relationship between the radius of the indenter and its load is established to achieve qualitative indices of the process of ultrasonic action. The state of the surface of steel parts by parameters of microhardness and structural components is studied. It is proved that ultrasonic treatment of agricultural machinery parts allows to increase microhardness of steel surfaces up to 27%. It is established that by changing the parameters of power and ultrasonic load, it is possible to control the formation of a hardened layer in the material.

numerical modeling, detail, influence, cylinder, theory, ultrasound, deformation, stress tensor, fatigue resistance, steel, indentor, microhardness

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