Preparation and properties research of Cu-based electrical contact composites containing Cr and NbSe₂

The Cu-based electrical contact composite materials containing Cr and NbSe₂ in the different mass fractions were prepared by repressing and reburning method in this study, and the mechanical, electrical, and tribological properties of copper-based electrical contact composites were investigated by optical electron microscope, X-ray diffractometer, hardness tester, and scanning electron microscope. The results show that, the density of the copper-based composites increases with the increase of NbSe₂ content, while the hardness and fracture strength increase with the increase of Cr content. The copper-based composites with the higher Cr content can easily generate the CuO nanoplates on the wear scar surface, which improves the tribological properties but reduces the electrical properties of the copper-based composite materials. Consequently, the copper-based composites containing Cr and NbSe₂ in the appropriate mass fraction show the better mechanical and electrical properties. Moreover, the tribological properties of the copper-based composites are also improved due to the synergistic effect of the NbSe₂ lubricating film and CuO nanospheres.