Modeling of Thermal Processes During Electrical Discharge Machining in Order to Determine Rational Processing Conditions

Abstract

The article presents a method for determining the rational modes of electrical discharge machining (EDM). The method is based on solving the thermal problem of moving the boundary of the material phase transformation (Stefan's problem) and calculating the depth of the holes formed on the surface of the workpiece from electrical discharges. In this case, the depth of the hole is equal to the depth of penetration of the material, and the molten material is completely removed from the workpiece. The density of the heat flux coming to the workpiece depends on the pulse energy of the generator, which is distributed between the anode, cathode, interelectrode gap, and is also spent on radiation and other losses. In this regard, it is important to determine the pulse energy coming directly to the workpiece. Currently, no exact correlation has been established between the pulse energy set by the generator and the heat flow acting on the workpiece. It is possible to determine the density of the heat flux coming on the workpiece by solving the inverse thermal problem: according to a known or specified melting depth of the material and the duration of the heat source. Thus, knowing the pulse energy of the generator, as a result of which the hole was formed, and the melting depth of the hole, it is possible to calculate the fraction of the pulse energy that falls directly on the workpiece. The article defines the proportion of generator pulse energy supplied to the workpiece, the achievable performance of the EDM process, the temperature distribution over the depth of the workpiece and the thickness of the thermally modified layer. Using the direct thermal problem, the melting depth of the material is determined depending on the energy and pulse duration, and the surface roughness is predicted

Please cite this article in English as:

Stavitskiy I.B. Modeling of thermal processes during electrical discharge machining in order to determine rational processing conditions. Herald of the Bauman Moscow State Technical University, Series Mechanical Engineering, 2026, no. 1 (156), pp. 57--73 (in Russ.). EDN: BXSWFG

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