pitsingukorroosiota

Pitsingukorroosiota is a term used in materials science and corrosion engineering to describe localized corrosion that forms discrete pits on a metal surface. It refers to a pit-type attack where small, deep openings develop at specific sites, contrasting with uniform thinning of the metal across the surface.

Initiation typically occurs at microstructural weaknesses or inclusions that disrupt the protective oxide layer. Chloride ions, acidic or near-neutral pH, and stagnant or low-oxygen conditions promote pit formation. Once a pit nucleates, it concentrates anodic dissolution and can grow rapidly, often under a rim of film that masks further attack.

Common environments include seawater and chloride-containing solutions, industrial brines, and other aggressive electrolytes, particularly at elevated temperatures or with poor fluid flow. Stainless steels, nickel-based alloys, and some aluminum alloys show susceptibility, with the degree of attack depending on composition, heat treatment, and residual stresses.

Detection relies on visual inspection, microscopy, and surface profilometry, supplemented by electrochemical tests such as potentiodynamic polarization to determine pitting potential. Prevention focuses on material selection with high pitting resistance, protective coatings, control of chloride exposure, and design strategies to avoid crevices and stagnant zones. Inhibitors and proper cleaning can further reduce risk.