ABSTRACT
The corrosion sensitivity of polycrystalline materials largely depends on their structural characteristics. Intergranular corrosion penetrates more directionally than grain corrosion, with the grain structure playing a crucial role. Rapid intergranular corrosion weakens grain connectivity, leading to grain detachment and increased localized corrosion depth, intensifying stress concentrations in engineering steels and accelerating fatigue crack initiation. This study investigates the grain detachment and corresponding corrosion evolution laws caused by intergranular corrosion under the influence of material structure. Using the Voronoi tessellation method, a model of polycrystalline materials is created, along with a corrosion simulation incorporating grain detachment effects using the cellular automaton method. Temporal evolution patterns of corrosion fronts and overall progression are statistically analysed. Comparative analysis with detachment-free models quantitatively reveals how grain detachment alters corrosion evolution process. This research advances intergranular corrosion modelling frameworks, offering improved numerical guidelines for corrosion prediction and steel durability assessments.
