During machine operation under conditions of aggressive environment, high temperatures and external forces, the role of diffusion is to provide a passive transport of aggressive and alloying components in the surface layer and to limit the intensity of corrosion process.
The coupled equations of mutual diffusion in a deformable solid were formulated. To describe the chemical composition of the local volume of the material, it was suggested to use variables that did not imply its closeness. The diffusion was described in a local diffusion frame of reference, which was related to markers and drifted relative to the material.
This description is based on a basic experiment and ensures an unambiguous solution to the thermodynamic inequality problem. The necessity for the hypothesis of motion decomposition into the convective and diffusive motions was justified.
Dudin D. S., Keller I. E. On the decomposition of motion in the description of interdiffusion in a viscoelastic body // Mechanics of Solids. 2024. Vol. 59, no. 7.