Corrosion performance of new Cu-V weathering steels in harsh industrial environments

Abstract

The structure and properties of weathering steels have a significant impact on the safety of practical applications and are also closely linked to localised corrosion induced by external elements. In this study, the structure and properties of weathering steels and corrosion mechanisms were investigated using various microtesting techniques, with a special study of the effect of copper elements on the corrosion of weathering steels and ordinary steel bars. Experimental data showed that HRB400aE (0.3% Cu) and HRB500aE (0.6% Cu) lost less weight in corrosion in the peri-immersion experiments compared to HRB400E and HRB500E when Cu and V elements were present. In electrochemical tests, HRB400aE (0.3% Cu) and HRB500aE (0.6% Cu) showed a smaller trend of potential decrease, slower rate of decrease, smaller self-corrosion currents and lower electrochemical activity than HRB400E and HRB500E. These results confirm the protective effect of trace alloying elements such as copper and vanadium on the corrosion resistance of steel bars in industrial atmospheres.