Weatherability of 09CuPCrNi steel in a tropical marine environment

The stability of weathering steel (09CuPCrNi) exposed at tropical marine environments for varied periods was investigated. The synergistic effect of exposure environment and alloy elements on weatherability was also studied. The classical weight loss method was used to evaluate weatherability, while the iron rust layers formed on weathering steel under different conditions were analyzed by using Infrared spectroscopy (IR), electron probe of mass analysis (EPMA) and electrochemical techniques. The results show that under low chloride deposition, the enrichment of Cr plays an important role on improving weatherability; conversely chloride ion is primary factor to whittle weatherability in high chloride deposition.