Titanium- and molybdenum-boride composite coatings on steels

Two steels with 0.36 and 0.95 mass % carbon content are coated with Fe-Ti-B and Fe-Mo-B composite coatings by thermodiffusional metallization with Ti and Mo and subsequent boronizing. The coatings consist of a FeB surface layer and a Fe 2 B sublayer, both Ti- and Mo-alloyed. The dry friction wear resistance of the 0.36 % C steel is improved by these coatings by a factor of 3 to 4. In the 0.95 % C steel, the formation of TiC and Mo2C disturbs the continuity of the interface between the coating and the substrate and the dry friction wear resistance is practically not improved. The Ti-B layers are of greater wear resistance compared to the Mo-B layers.