OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 27 No. 2 2025 Fig. 8. Relationship between median corrosion damage depth hm and hp a b Fig. 9. Microstructure of Sample No. 4 (a) and Sample No. 5 (b), showing the highlighted area of corrosion initiation The grain shape can be evaluated by its degree of anisotropy, which increases with plastic deformation of the material [22]. Plastic deformation in a phase with a body-centered cubic (BCC) lattice most commonly leads to slip along crystallographic planes and directions {110} <111> [31]. This accounts for the described process. Due to the change in grain shape, there is a decrease in internal residual stresses as a consequence of the appearance of stresses of opposite sign [28]. The resulting anisotropy of texture and material properties affects the corrosion fracture process (Fig. 10). The correlation between corrosion processes and internal stresses, arising during plastic deformation, is due to the modification of the defect substructure of crystalline material, realized through the activation of dislocation dynamics. This mechanism involves the coordinated slip of linear defects in the crystal lattice along preferred slip systems, determined by the crystallographic configuration with maximum atomic packing density, which minimizes the activation energy for shear processes [21, 32-33]. Plastic deformation induces directed migration of dislocations, accompanied by their interaction within the bulk of the material, including annihilation upon encountering dislocations of opposite sign, as well as the formation of stabilized configurations (dislocation walls, networks) [21, 32-33]. These structural transformations modulate local electrochemical potentials, creating regions of enhanced reactivity, which catalyzes corrosion processes, as seen in Fig. 11. This occurs due to the following factors: – formation of microgalvanic couples between deformed and undeformed regions;
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