Study on the tribological properties of MoB/Cu laminated composite materials fabricated by hot-pressing process

This work presents a novel method for fabricating MoB/Cu laminated composite materials which are distinguished by their strong interlayer bonding and unique microstructure. MoB ceramic layer can obviously improve the friction and wear properties of Cu matrix composites. The tribological properties on cross-sections of MoB/Cu laminated composite are studied with GCr15 (a typical high-carbon chromium bearing steel) ball as counterpart under dry friction conditions. When the friction angle is less than 30°, the wear rate (∼0.4974 × 10^-4mm³/(N·m)) is reduced substantially by about 85 % compared to pure copper. The coefficient of friction of the composite ranges from 0.182 to 0.223 at a friction angle from 0° to 90°. A dense lubricating oxide film is formed during the friction process, effectively slowing down the adhesive wear and increasing the friction and wear resistance. After XPS (X-ray photoelectron spectroscopy) analysis, the main components of the lubricating film generated during the friction process are MoO₃, B₂O₃, Al₂O₃, CuO, and Fe₂O₃.