EXTREMELY DEFORMED SINTERED COPPER NANOCOMPOSITES STRUCTURE AND PROPERTIES EVOLUTION

The purpose of the work is to determine the structure and mechanical properties of sintered copper (including those containing carbon nanotubes) after intensive plastic deformation by torsion. Methodology: The research objects are samples of copper powder PMS-1 (GOST 4960-75), copper powder with a 45 microns’ fraction, copper powder PMS-1 with the carbon nanotubes addition 1 % by weight, manufactured by double pressing − sintering, with a 700 MPa final pressure, temperature of 950 °C, and subjected to intensive plastic deformation by torsion on a Bridgman anvil. The structure is investigated using a Tescan Micra 3 LMU scanning electron microscope. Micromechanical tests were carried out using the “Micron – Gamma” device. Originality. At first, the microstructure and mechanical properties of sintered copper and nanomaterial “copper − carbon nanotubes” after intensive plastic deformation by torsion were investigated. It has been established that intensive plastic deformation by torsion significantly affects the sintered copper samples structure and mechanical properties. The sintered copper grain shape changes from approximately spherical to elongated in the deformation direction, and the grain size decreases by 5−7 times. In the case of “copper + 1 % CNT” nanomaterial intensive deformation, the grain refinement effect is significantly less pronounced. A significant increase in the mechanical properties of sintered copper during intensive plastic deformation has been established. The highest indicators were obtained for the “copper + 1 % CNT” nanomaterial. Practical value. The results of the work can be used in the manufacture of copper products for electrical and thermal purposes with increased wear resistance.