Surface Topography of Arc-Sprayed Coatings by Cored Wires of Different Compositions and Its Influence on the Wear Mechanism

The purpose of this work is to study the influence of the components of the composition of powder wires on the surface characteristics of sanded electric arc coatings. For the application of coatings used electric spray and powder wires with a diameter of 1.8 mm containing powders FeSi, FeTi, FeMn, pure metals Al and Cr and carbide B4C with a filling factor reached 24%. Spray parameters: current – 150 A, voltage – 32 V, air stream pressure – 0.6 MPa, spray distance – 120 mm. The surface topography revealed the plate structure of the coating with slats of different chemical composition. In coating are presence of carbides and borides, a significant amount of iron oxides and oxides of alloyed elements at the slats. Provisions from a considerable height contribute to intense wear due to reducing the friction steam surface. The interaction is regulated by the ratio of the depth of the projections (H) to the radius of its sharp tip (r). When H/r <0.02, there is only elastic interaction, with the material of counteraction elastic. In the range of 0.02 < H/r <0.7, the projections induce plastic deformation of the counter-body. If H/r > 0.7, sharp projections are cut to the surface, generating micro -cutting. Reducing the number and size of inclusions and increasing their rounding radii are critical for improving wear resistance. The coating contains complex mixtures of Fe-Cr oxide. The connection of chromium and aluminum oxides resist cutting, they will either break, forming surface ulcers or residual projections. Adding a ferromanganese to the wires produces manganese oxides with low micro -Service, which do not form the cutting of the edges during friction. Titanium applications that respond quickly with oxygen leads to a subtle formation of dispersed oxide inclusions based on those (7 GPa). These manganese and titanium oxides do not generate sharp cutting edges, reducing the surface roughness of making the coating more suitable for use in friction pairs.