Corrosion Inhibition Characteristics and Mechanical Properties of High‐Strength Galvanized Steel Wire in the Presence of N,N′‐Dimethylethanolamine

ABSTRACT High‐strength galvanized steel wire (HSGSW), as a critical load‐bearing component in bridge cable systems, is highly susceptible to environmental corrosion during long‐term service, posing significant threats to the safety and durability of bridge structures. To address this issue, this study systematically investigates the corrosion behavior and mechanical performance degradation of HSGSW in the presence of N,N′‐dimethylethanolamine (N,N′‐DMEA), an organic corrosion inhibitor. Electrochemical accelerated corrosion tests combined with weight loss measurements were conducted to quantitatively evaluate the inhibition efficiency of N,N′‐DMEA under varying concentrations and exposure durations. SEM and EDS were employed to characterize the microstructural evolution and surface chemical composition of corroded specimens. The effects of corrosion inhibition treatment on the mechanical degradation of HSGSW were further analyzed based on load–displacement curves obtained from tensile tests. The results indicate that N,N′‐DMEA forms a protective adsorption film on the steel surface, significantly enhancing corrosion resistance, with an optimal inhibitor concentration of 0.08 mol·L −1 . As corrosion progresses, the corrosion products evolve into a dark, porous structure primarily composed of Fe, leading to the formation of localized pits and inducing stress concentration, which alters the fracture mode from a typical cup‐and‐cone morphology to a mixed splitting–milling fracture. Inhibitor concentrations not exceeding 0.08 mol·L −1 show a positive correlation with inhibition efficiency, while increased current density results in reduced efficiency. Notably, under equivalent corrosion conditions, specimens treated with the inhibitor exhibited significantly higher ultimate tensile strength than untreated ones, with an estimated service life extension of approximately 150%. This study provides a novel technical approach for the corrosion protection of HSGSW used in bridge cables and offers valuable engineering guidance for ensuring the long‐term safe operation of cable‐supported bridges.