Equilibrium and Non-Equilibrium Models of Layer Formation during Plasma and Gas Nitriding

Equilibrium and non-equilibrium models of γ'-Fe 4 N growth during nitriding are considered in an attempt to explain the differences observed in the growth of this phase during glow discharge plasma nitriding and gas nitriding. Calculated results taking account of cathode sputtering agree well with experimentally observed ones. Solutions for the non-equilibrium model approach those of the equilibrium model when mobility of the γ'/α interface approaches infinity.