A dimensionless compatibility criterion of diffusion coatings with a metallic base

The behavior of alloying elements is considered in the case of diffusion saturation of alloys by mobile elements. The experimentally observed increase or decrease in the concentration of alloying elements at the diffusion coating-base interface is explained. A mathematical model of the process is suggested; the corresponding estimates coincide with experimental results. A dimensionless compatibility criterion of coatings with the base is suggested that characterizes the degree of variation of the concentration of alloying elements at the coating-base interface. Numeric values of this criterion are determined that point to the field of its possible application.