Different additives (metals, ceramics, and metal/ceramic assembles) were incorporated into chromium oxide (Cr2O3) coatings to improve its wear resistance. The doping or co-doping effects were compared in terms of the microstructure, phase composition, microhardness and sliding wear properties of plasma-sprayed Cr2O3-7wt.% Mo, Cr2O3-7wt.% Nb2O5, Cr2O3-4wt.% MoO3-3wt.% Mo, and Cr2O3-4wt.% Nb2O5-3wt.% Mo coatings. Under the low sliding loads, the composite coatings mated with WC-Co counterparts have lower friction coefficients than those against Si3N4, which are inverse with their microhardnesses...
