Gradient structural-phase states and properties of surface layer after nitro-oxidation

The phase equilibrium is considered, the formation of nitride phases during gas nitriding due to presence carbon in iron steel matrix all formed structural-phase states layer, carbides are released, dispersion and which layer depends on nitrogen potential saturating atmosphere. During subsequent oxidation water vapor, simultaneously with a surface oxide film exposure period, especially vapor additives complexion agents, reaction-diffusion, gradient low-nitrogen carbonitride, oxycarbonitride, layer. At same time, oxygen furnace atmosphere positively affects internal zone. corrosion resistance nitride-oxide diffusion coatings consisting magnetite ratio modified nitrides γ ' -phase composition. composition oxycarbonitrides larger proportion has highest lower rate development damage surface. providing positive property gradient, can provide conditions for external friction sliding friction.