The Performance of Accelerated Testing Methods for the Evaluation of Weathering Steels

Review article, 2026

Weathering steel (WS), a class of low-alloy steel, which often outperforms traditional carbon steels in bridge applications, develops a stable and adherent patina that enhances resistance to atmospheric corrosion. The patinas develop through complex electrochemical and physicochemical reactions between steel alloying elements and environmental constituents such as pollutants, oxygen, moisture, chlorides, and sulfur compounds. However, real-life field exposure tests to evaluate the performance of weathering steel in rural, urban, industrial, and marine environments are costly, time-consuming, and inconsistent, prompting the need for accelerated laboratory-based corrosion tests. This paper compiles and thoroughly examines the effectiveness of widely used accelerated corrosion testing techniques, such as ISO 16539 (Synthetic Ocean Water), Cebelcor, Prohesion (ASTM G85), Salt Spray (ISO 9227), Kesternich, and others, in simulating the weathering behavior of weathering steel. Findings show that some accelerated cyclic tests can partially replicate protective patina formation in polluted or sulfate-rich environments, whereas others, such as continuous salt spray, tend to overestimate corrosion due to the absence of key environmental factors such as wet/dry cycles, microbial activity, UV radiation, and wind-driven rain. Existing tests do not adequately replicate real-world steel–environment interactions. This review proposes a multidisciplinary approach combining localized wet/dry cycles, advanced environmental chambers, and microstructural and oxide layer analysis with AI (artificial intelligence)/ML (machine learning) for predictive models to improve test relevance and long-term performance forecasting of weathering steels.