Volgograd State Technical University, Volgograd, Russia

N. A. Kidalov, Head of the Department ofMachinery and Foundry Technology, Doctor of Technical Sciences, Professor
N. Yu. Miroshkin, Head of the Laboratory of the Department of Machinery and Foundry Technology, Candidate of Technical Sciences, e-mail: nikolays34rus@gmail.com
A. A. Belov, Associate Professor of the Department ofMachinery and Foundry Technology, Candidate of Technical Sciences
S. R. Polyak, Postgraduate Student of the Department of Machinery and Foundry Technology

The work is devoted to solving the problem of obtaining metal-filled compo site materials based on graphite with specified physical and mechanical properties without the use of expensive equipment and significant energy consumption, which directly affect the cost of final products used in various industries (sliding current-removing contacts of electric motors and electric vehicles). The use of an electrochemical method for forming an internal copper frame in the open pores of a graphite base instead of traditional methods based on impregnating blanks under conditions of high overpressure and temperature corresponding to the melting point of the reinforcing metal will make it possible to obtain a competitive composite material with high performance properties and lower cost. To do this, it is necessary to fill the open pores of the graphite matrix with a solution of a copper electrolyte. It is shown that during degassing of porous blanks in an aqueous solution of sulfuric acid electrolyte for 10 minutes, followed by exposure to vacuum for 180 minutes, the filling of the open pores of the matrix reaches 25%, and during ultrasonic treatment it reaches 91% during the first 60 minutes. Subsequent electrochemically applied copper coating made it possible to form a thin metal layer on the surfaces of the open pores of the matrix throughout its volume, which is confirmed by the microstructure of the resulting material. The material created in this way, due to the formation of an additional internal copper frame in the form of a thin-walled metal shell on the inner surfaces of the open pores, showed a decrease in electrical resistivity by 74.29% compared with the initial one.
The research was carried out at the expense of the funds of the VolgSTU development program “Priority 2030”, as part of the scientific project No. 8/648-24.

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