Berezhanskyi T. Formation of secondary structures during wear of eutectic coatings

In thesis actual scientific and technical problem was solved – phase composition of friction-induced layer was determined (in depth from the friction surface towards the core) and a new eutectic coating based on Fe-Mn-CB-Si alloy doped with Cr was invented. This alloy may be used for formation of surface layers of special purpose equipment parts. A generalized tribochemical models of these eutectic coatings wear was proposed. The tribological researches, as well as hardness, microhardness, nanoscale, topography of the friction surface, and the study of SIMS and XPS for determining the quantitative and qualitative composition of the technological and operational surface layer have been carried out. The change in the composition of the friction surface was determined by the segregation of the atoms C, B and Si on the surface of friction and formation as a result of the tribosynthesis of secondary structures (nanostructures), which increase the wear resistance of the surface layer. The protective eutectic coating on the basis of the Fe-Mn-C-B-Si system, doped with Cr, allowed to increase the durability of the hydraulic rescue knives "Hydrum H-32" by ~ 1.8 times, the pump of a fire truck by ~ 2.4 times and the compressor LB50 repair interval by ~ 3 times. A generalized model of deterioration of the surface layer is proposed.