Sintered Steels Coated with a Chromium Layer Doped with Diamond Nanoparticles

Electrochemical Cr coatings doped with diamond nanoparticles were deposited on sintered steels with different carbon contents (0.2-0.8 wt.-%). The mechanical properties of surfaces as hardness and wear resistance increase as compared to the steel substrate. Microcutting and microgridding mechanisms were observed after tribological tests, but also adhesive wear in some areas was observed. X-ray examination indicated that the layer was textured, with the exception of the sample with the highest concentration of diamond nanoparticles in the electrolyte (42 g/l). The intensity ratio I_Cr110/I_Cr200 was calculated and compared with the indices for a standard sample. The greatest differences in the intensity ratio occurred for the samples with low carbon content (0.2% C). On the other hand, more the material is textured the greater the difference.