Mechanical and tribological properties of Cr/Cr2O3 multilayer films

Cr/Cr2O3 multilayer and single-layer films were deposited through multiple arc ion plating technique. The influence of modulation ratio on the mechanical and tribological properties was also investigated. Results show that the multilayer design of Cr/Cr2O3 films could improve the toughness of films, but a certain degree of hardness loss is also observed. The hardness and adherence strength are improved with the increase of Cr2O3 layer thickness. Furthermore, alternating layers of ductile soft metals and hard ceramics could suppress the propagation of microcracks and brittle fracture. However, the decrease of modulation ratio could causes a decline in the mechanical properties. The film with appropriate modulation ratio (Cr2O3:Cr ratio 10:1) exhibits better comprehensive properties than other films, this film also exhibits an excellent wear resistance with a high load of 10 N. Consequently, the wear life is improved from 6 m of the single-layer Cr2O3 film to 835 m of the multilayer film.