Microstructure and Current Carrying Wear Behaviors of Copper/Sintered–Carbon Composites for Pantograph Sliders

Neoteric copper/sintered–carbon (Cu/SC) composites for pantograph sliders were produced with the method of pressure infiltration. The friction and wear behaviors with or without current and mechanical performances of Cu/SC composites showed that graphite acted dual effects on Cu/SC, that is, with the addition content of graphite, the electrical conductivity of carbon matrices increased while the mechanical properties decreased. The friction coefficient and the wear rate decreased with the increase of the graphite content on dry sliding wear test, and the minimum friction coeffient was only 0.096. Meanwhile, the friction coefficient increased first and then decreased with the current increse, while the wear rate just kept increasing. Scanning electron micrographs revealed a grid-like distribution of copper in the Cu/SC composites. Futhermore, through observation and analysis, it was found that Cu/SC composites of pantograph sliders were dominated by adhesive wear and corrosive wear respectively under two different currents of 5 A and 15 A. Graphic Abstract Copper was uniformly distributed in the carbon matrix in a spatial network structure, almost filling the pores in the matrix, greatly improving the overall combined by mechanical interlocking, and the compressive strength is up to 159.81 MPa.