Corrosion initiation and long-term corrosion behavior of weathering steel with rare earth (RE) addition in marine atmosphere

Abstract

This study systematically explores the corrosion resistance of weathering steel with rare earth (RE) addition in simulated marine atmospheric environment. Both the corrosion initiation and long-term corrosion behavior were investigated by multifarious analytical techniques, including electrochemical measurement, scanning electron microscope/energy dispersive spectroscopy (SEM/EDS), salt spray test, laser scanning confocal microscope and Raman spectroscopy. Results show that RE elements can refine grains and modify inclusions. Nonetheless, the corrosion initiation of weathering steel with RE addition cannot be inhibited since the dissolution of steel matrix was more significant than the inclusions-induced corrosion during this stage. Besides, RE addition significantly improves the long-term corrosion behavior of weathering steel under salt spray testing conditions, which simulates a marine atmospheric environment with chloride deposition rate of 36.40 mg/m2·day. The results show that the weathering steel with RE addition hold promising potential for building structures in marine atmosphere.