Effect of annealing on wear resistance and electroconductivity of copper processed by high-pressure torsion

Abstract

The influences of annealing temperature on the wear properties and electrical conductivity of Cu were studied after processing by high-pressure torsion (HPT). The annealing of Cu specimens processed by HPT leads to an increase in electroconductivity and a decrease in the wear rate. It is apparent that a nanotribolayer at the surface induced during wear sliding plays a more significant role than the ultrafine-grained structure. A slight increase was observed in the microhardness of HPT copper specimens upon annealing at a relatively low temperature (100°C), and this is most likely due to a change in texture. The annealing leads to an increase in the Taylor factor by *5 %, which is in good agreement with the increase in the microhardness level which is also by *5 %. It is apparent that low-temperature annealing of HPT copper may produce optimal properties of the specimens including high strength and electroconductivity with a lower wear rate.

Effect of High‐Pressure Torsion on Hardness and Electrical Resistivity of Commercially Pure Cu

“…As shown in Figure a, the refined grain size of 1.5 μm increased slightly to 2.5 μm at the onset of HPT straining and rapidly decreased to a saturated value of ≈300 nm after the HPT strain of ≈40. This is consistent with other studies showing the measured grain sizes of a few hundred nanometers in Cu by HPT processing . The value of l LAGB decreased monotonically up to a strain of 3 and remained low up to a strain of 5; thereafter, it increased to saturate with the HPT processing.…”

Electrical conductivity and mechanical properties of Cu-0.7wt% Cr and Cu-1.0wt% Cr alloys processed by severe plastic deformation

“…During the past two decades the microstructure, mechanical and physical properties of bulk UFG and nanocrystalline (NC) metallic materials are studied in large amount of papers [1][2][3][4][5][6][7][8]. Therefore, the fields for further development related to Cu-Cr alloys span a wide range of different applications [9][10][11] in the electrical industry. Nevertheless, it is clear that for the fabrication of advanced installations for electrical conduction from Cu-Cr alloys use, there is a need to produce an UFG or NC microstructure with high electrical conduction properties and suitable high wear resistance (WR) and low coefficient of friction (COF) at temperature increase.…”

“…have been studied. Unfortunately, the results in [9][10][11][12][13][14][15] were inconsistent because the wear tests were conducted using different methods and different parameters. In this investigation, we study the dependence of Cu-Cr alloys tribological properties on its microstructural state as well hardness.…”

Effect of HPT processing followed by long term natural ageing on mechanical and electrical properties of commercially pure Cu

“…Accordingly, this study focuses on evaluating effects of natural ageing on different properties of commercially pure Cu, which is one of the materials that is used for applications where a diverse set of properties, such as yield as well as ultimate tensile strength, electrical conductivity, etc., is important. It should be noted that HPT processed Cu exhibits good mechanical properties without losing its electrical properties, especially in the as-processed condition [7,8].…”