On modeling of stress‐induced diffusion within micropolar and classical approaches

Abstract

The paper continues and summarizes our previous investigation on a description of the local increase of hydrogen in the vicinity of the border of a metal specimen after hydrogenation. The local increase is observed after artificial saturation of metal specimens and after operation of metal details in corrosive environments. It can worsen significantly the material properties and its behavior at the macro-level. A stress-induced diffusion process in a cylinder is modeled. The paper accounts for the inner stresses and strains by means of chemical potential and by means of the dependence of the diffusion coefficient on elastic strain energy. The stress-strain state is determined within the micropolar theory of elasticity, the results are compared with the ones obtained within the classical theory.Nonuniform fields of stresses and strains result in a nonuniform distribution of hydrogen. Accounting for the couple stress interactions between continuum particles results in a faster saturation of the boundary layer with hydrogen.