THEORETICAL STUDIES OF THERMAL PROCESSES IN ELECTROLYTIC-PLASMA HARDENING

This article examines the theoretical aspects of thermal processes occurring during electrolytic-plasma hardening (EPH), including the analysis of temperature fields and heating rates. The finite difference method was used for numerical modeling, allowing for a more precise determination of the temperature distribution in the treated material. The heat transfer problem in a flat plate with a thickness of 15 mm was considered, where the boundary conditions were as follows: on one boundary, heating was carried out by a surface thermal flux from the electrolyte plasma, while on the opposite side, heat was dissipated through convection in an air medium. The calculations revealed non-uniform temperature distribution over time and depth, confirming the formation of three distinct structural zones: the hardened zone, the heat-affected zone, and the base matrix. The temperature of the samples during the experiment was measured using a thermocouple positioned 2 mm from the heated surface. Experimental data obtained from the treatment of 45 steel samples confirmed the accuracy of the numerical modeling. The research results demonstrate the effectiveness of numerical modeling, including the finite difference method, in optimizing EPH parameters, thereby reducing the volume of experimental work and lowering technology development costs. The obtained data can be used to improve surface hardening technologies for structural steel components used in agricultural machinery, mechanical engineering, and other industries. The study confirms the potential of EPH for enhancing the operational characteristics of steel products.

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