Enhanced Corrosion and Tribological Properties of GO-Reinforced Cu Matrix Nanocomposites Fabricated by ARB Process
摘要
In this study, microstructure, corrosion behavior, and tribological properties of Cu–GO nanocomposites produced by accumulative roll bonding (ARB) process up to 4 cycles have been studied through microstructure observation, microhardness testing, pin-on-disk wear-testing, and electrochemical measurements in 3.5-wt pct NaCl solution. Microstructural studies show ARB can remarkably decrease the grain size and improve the dispersion of GO in the Cu matrix as well as the connection improvement between Cu layers. It is observed that the highest hardness value of about 140 HV is obtained with the increasing number of cycles up to 4 due to the strain-induced grain refinement and presence of secondary phase GO. Moreover, wear rate and weight loss of the samples were continuously decreased up to cycle 2 and after that they were grown and delamination wear became the dominant mechanism with increasing the ARB cycles. In addition, corrosion behavior shows that the corrosion current density (0.7 × 10−3 A cm−2) of the nanocomposite was decreased after 4 cycles and the best anti-corrosion property for forming the passive films was provided. The coarse microstructure in Cu-annealed sheet leads to accelerating galvanic corrosion.