A Peridynamic Model for Crevice Corrosion Damage

Abstract

A new peridynamic (PD) model for crevice corrosion damage is introduced and cross-validated with experimental results reported in the literature. The model defines a simple metal ion concentration-dependent corrosion rate along the metal-electrolyte interface. Crevice problems have ratios of gap-to-length of 1/100 or lower. To increase the computational efficiency when having a domain with an extreme aspect ratio, the PD formulation with spherical horizons is modified to accommodate arbitrary-shape horizons. The model is validated against experimental results on immersed bolted washers. The PD simulations predict the observed corrosion kinetics, and the deepest corrosion trenches form at a critical distance from the mouth of the crevice. The location of the most severe corrosion attack does not have to be specified as an input. Instead, it results directly from solving the problem with PD. The evolution of crevice corrosion damage is autonomous in PD, and only the geometry, initial, and boundary conditions control the evolution of the corrosion process.