Study of the EDM Process of Bimetallic Materials Using a Composite Electrode Tool

New types of profile products make complex use of bimetals. These materials possess a set of properties such as strength, corrosion resistance, thermal conductivity, heat resistance, wear resistance. For the processing of such products, it is advisable to use electrophysical processing methods, one of which is the technology of copy-piercing electrical discharge machining (EDM). Currently, EDM is one of the most common methods for processing products from modern bimetal materials. An urgent task is to study the EDM process of bimetallic materials. The aim of the work was to increase the efficiency and accuracy of the EDM process of bimetallic products using electrode-tools with different physical and mechanical properties. Bimetal—weld coated steel backing, base material—09G2S steel, surfacing material—M1 copper were used. The processing of the bimetallic workpiece was carried out on an Electronica Smart CNC copy-piercing EDM machine. EI used graphite, copper, and composite. A theoretical model was developed that allows calculation of the amount of removal of bimetallic material of steel–copper depending on the EDM modes and the ET (electrode tool) material. During the processing of the steel layer, regardless of the EI material, microcracks were formed along the grain boundaries, and during the processing of the copper layer, enlarged holes resulted.