OXIDATION RESISTANCE OF STEEL SURFACE LAYER ALLOYED BY Mo AND Cr UNDER THE ACTION OF COMPRESSION PLASMA FLOWS

The phase and element composition, microhardness of the carbon steel surface layer simultaneously alloyed with molybdenum and chromium atoms under the impact of compression plasma flows and subsequent annealing in air were investigated in this work. An X-ray diffraction analysis, scanning electron microscopy, energy dispersion microanalysis, and microhardness measurements were used as investigation techniques. The findings showed that the alloyed layer contained solid solutions on the basis of α-Fe and γ-Fe. An alloyed steel surface layer possessed better oxidation resistance at 400oC being compared with initial steel. Annealing resulted in the formation of an oxidized layer consisting of Fe2O3 and Fe3O4 phases. The presence of alloying elements like Mo and Cr was observed in this layer