A research on the electrical sliding behavior wear of dual-scale particulate reinforced copper matrix composites

This work aims to investigate the electrical sliding wear behavior of the dual-scale particulate reinforced copper matrix composites by a self-developed pin-on-disk wear tester. Cu-xCr-0.3Zr-1ZrB2 (x = 0, 0.5, 1.0) composites were fabricating by casting and cold rolling. The microstructure of worn surfaces was examined using scanning electron microscopy (SEM) and laser scanning confocal microscope to unravel the wear mechanisms. The results indicated that the combined effect of mechanical wear and electrical wear dominated the wear process with an increase in the apparent normal load. Amplifying the electrical current increased the wear loss of the sliding pair, in the meantime alleviated the fluctuation of the friction coefficient with marginal changes in the average values. After introducing Cr element and ZrB2 particles, the wear rate decreased from 0.197 mg/m to 0.141 mg/m under moderate operating test conditions. Adhesive wear and abrasive wear occupied an important position in the wear mechanism of the Cu-1wt%Cr-0.3wt%Zr-1wt%ZrB2 composite under electrical current due to the elevation of thermal stability and the formation of a tribolayer introduced by these reinforcements.