Introduction. In modern engineering, there are increasing demands for processing performance, which ensures high quality results for the processed surface of products made of alloyed wear-resistant steels. These steels have high physical and mechanical properties, which makes its machinability with a blade tool rather difficult. For the processing of such products, it is advisable to apply electrophysical processing methods, one of which is the technology of electrical discharge machining (EDM). With the help of EDM, it is possible to process difficult-to-reach deep elements with a complex profile, as well as blind grooves of products made of alloyed wear-resistant steels. The paper deals with effectiveness improvement of EDM processing of complex profile elements of the “Shutter Housing” type parts made of steel 38Cr2Ni2MnA (GOST 8479-70). Subjects of research are the following: the parameter of the roughness of the treated surface; performance and accuracy of steel 38Cr2Ni2MnA EDM with different modes. The aim of the work is to increase the efficiency and accuracy of EDM of blind grooves and elements of a complex profile of products made of alloyed wear-resistant steels. Methods. Experimental studies are carried out according to the method of a full factorial experiment with subsequent regression analysis. For carrying out of experiments, a Smart CNC EDM machine is used. A profile copper electrode is used as an Electrode-tool (ET). ET material is M1 grade copper (GOST 1173-2006). Results And Discussion. Empirical dependences, reflecting the relationship between processing modes, productivity, surface roughness parameter after processing, and the size of the interelectrode gap are established. To ensure the required ratios of the quality of the treated surface with maximum performance indicators, technological recommendations of the EDM of blind grooves and elements of a complex profile of products made of wear-resistant alloyed steel 38Cr2Ni2MnA, which has high rates of wear resistance, are obtained. The dimensions of the profile ET, taking into account the size of the side and end interelectrode gaps, providing the specified EDM accuracy, are calculated.
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Funding
This work is supported by a grant of the President of the Russian Federation for state support of young Russian doctors of science No. MD-1779.2019.8.
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