The paper discusses the results of research on the structure and tribological properties of hybrid layers
produced on the surface of medium-carbon steel in hybrid treatment, combining gas carburizing process with
the next treatment, i.e. diffusion chromizing and PVD treatment. A comparison was made of the structure
and tribological properties of the layers obtained as a result of hybrid treatment with the layers produced in a
single diffusion chromizing process. The studies of the layers concerned their structure, chemical composition,
thickness, and hardness. Linear wear of the layers were performed by means of three-cylinder-cone method.
It has been shown that the linear wear of samples with hybrid layers, produced on medium carbon steel, is
less than 50% of samples with single carbide layers. This indicates very good anti-wear properties of hybrid
layers.